[maven-release-plugin] prepare for next development iteration
diff --git a/angular/pom.xml b/angular/pom.xml
index 6c6c9ab..f3af2e5 100644
--- a/angular/pom.xml
+++ b/angular/pom.xml
@@ -22,14 +22,14 @@
   <parent>
     <artifactId>zeppelin</artifactId>
     <groupId>org.apache.zeppelin</groupId>
-    <version>0.5.6-incubating</version>
+    <version>0.5.7-incubating-SNAPSHOT</version>
     <relativePath>..</relativePath>
   </parent>
 
   <groupId>org.apache.zeppelin</groupId>
   <artifactId>zeppelin-angular</artifactId>
   <packaging>jar</packaging>
-  <version>0.5.6-incubating</version>
+  <version>0.5.7-incubating-SNAPSHOT</version>
   <name>Zeppelin: Angular interpreter</name>
   <url>http://zeppelin.incubator.apache.org</url>
 
diff --git a/cassandra/pom.xml b/cassandra/pom.xml
index 4e17ac9..8c3e30b 100644
--- a/cassandra/pom.xml
+++ b/cassandra/pom.xml
@@ -20,14 +20,14 @@
     <parent>
         <artifactId>zeppelin</artifactId>
         <groupId>org.apache.zeppelin</groupId>
-        <version>0.5.6-incubating</version>
+        <version>0.5.7-incubating-SNAPSHOT</version>
         <relativePath>..</relativePath>
     </parent>
 
     <groupId>org.apache.zeppelin</groupId>
     <artifactId>zeppelin-cassandra</artifactId>
     <packaging>jar</packaging>
-    <version>0.5.6-incubating</version>
+    <version>0.5.7-incubating-SNAPSHOT</version>
     <name>Zeppelin: Cassandra</name>
     <description>Zeppelin cassandra support</description>
     <url>http://zeppelin.incubator.apache.org</url>
diff --git a/elasticsearch/pom.xml b/elasticsearch/pom.xml
index a9e1203..d3625e0 100644
--- a/elasticsearch/pom.xml
+++ b/elasticsearch/pom.xml
@@ -22,14 +22,14 @@
   <parent>
     <artifactId>zeppelin</artifactId>
     <groupId>org.apache.zeppelin</groupId>
-    <version>0.5.6-incubating</version>
+    <version>0.5.7-incubating-SNAPSHOT</version>
     <relativePath>..</relativePath>
   </parent>
 
   <groupId>org.apache.zeppelin</groupId>
   <artifactId>zeppelin-elasticsearch</artifactId>
   <packaging>jar</packaging>
-  <version>0.5.6-incubating</version>
+  <version>0.5.7-incubating-SNAPSHOT</version>
   <name>Zeppelin: Elasticsearch interpreter</name>
   <url>http://www.apache.org</url>
 
diff --git a/flink/pom.xml b/flink/pom.xml
index c7e88c4..db35cba 100644
--- a/flink/pom.xml
+++ b/flink/pom.xml
@@ -22,14 +22,14 @@
   <parent>
     <artifactId>zeppelin</artifactId>
     <groupId>org.apache.zeppelin</groupId>
-    <version>0.5.6-incubating</version>
+    <version>0.5.7-incubating-SNAPSHOT</version>
     <relativePath>..</relativePath>
   </parent>
 
   <groupId>org.apache.zeppelin</groupId>
   <artifactId>zeppelin-flink</artifactId>
   <packaging>jar</packaging>
-  <version>0.5.6-incubating</version>
+  <version>0.5.7-incubating-SNAPSHOT</version>
   <name>Zeppelin: Flink</name>
   <description>Zeppelin flink support</description>
   <url>http://zeppelin.incubator.apache.org</url>
diff --git a/hive/pom.xml b/hive/pom.xml
index ffbbcf4..9360d88 100644
--- a/hive/pom.xml
+++ b/hive/pom.xml
@@ -22,14 +22,14 @@
   <parent>
     <artifactId>zeppelin</artifactId>
     <groupId>org.apache.zeppelin</groupId>
-    <version>0.5.6-incubating</version>
+    <version>0.5.7-incubating-SNAPSHOT</version>
     <relativePath>..</relativePath>
   </parent>
 
   <groupId>org.apache.zeppelin</groupId>
   <artifactId>zeppelin-hive</artifactId>
   <packaging>jar</packaging>
-  <version>0.5.6-incubating</version>
+  <version>0.5.7-incubating-SNAPSHOT</version>
   <name>Zeppelin: Hive interpreter</name>
   <url>http://www.apache.org</url>
 <!--
diff --git a/ignite/pom.xml b/ignite/pom.xml
index 8399e52..bc040e7 100644
--- a/ignite/pom.xml
+++ b/ignite/pom.xml
@@ -22,13 +22,13 @@
   <parent>
     <artifactId>zeppelin</artifactId>
     <groupId>org.apache.zeppelin</groupId>
-    <version>0.5.6-incubating</version>
+    <version>0.5.7-incubating-SNAPSHOT</version>
     <relativePath>..</relativePath>
   </parent>
 
   <artifactId>zeppelin-ignite</artifactId>
   <packaging>jar</packaging>
-  <version>0.5.6-incubating</version>
+  <version>0.5.7-incubating-SNAPSHOT</version>
   <name>Zeppelin: Apache Ignite interpreter</name>
   <url>http://zeppelin.incubator.apache.org</url>
 
diff --git a/kylin/pom.xml b/kylin/pom.xml
index d5a0f8a..46f82f1 100755
--- a/kylin/pom.xml
+++ b/kylin/pom.xml
@@ -21,14 +21,14 @@
     <parent>
         <artifactId>zeppelin</artifactId>
         <groupId>org.apache.zeppelin</groupId>
-        <version>0.5.6-incubating</version>
+        <version>0.5.7-incubating-SNAPSHOT</version>
     </parent>
     <modelVersion>4.0.0</modelVersion>
 
     <groupId>org.apache.zeppelin</groupId>
     <artifactId>zeppelin-kylin</artifactId>
     <packaging>jar</packaging>
-    <version>0.5.6-incubating</version>
+    <version>0.5.7-incubating-SNAPSHOT</version>
     <name>Zeppelin: Kylin interpreter</name>
     <url>http://zeppelin.incubator.apache.org</url>
 
diff --git a/lens/pom.xml b/lens/pom.xml
index b4f8ac2..fdedf78 100644
--- a/lens/pom.xml
+++ b/lens/pom.xml
@@ -22,14 +22,14 @@
   <parent>
     <artifactId>zeppelin</artifactId>
     <groupId>org.apache.zeppelin</groupId>
-    <version>0.5.6-incubating</version>
+    <version>0.5.7-incubating-SNAPSHOT</version>
     <relativePath>..</relativePath>
   </parent>
 
   <groupId>org.apache.zeppelin</groupId>
   <artifactId>zeppelin-lens</artifactId>
   <packaging>jar</packaging>
-  <version>0.5.6-incubating</version>
+  <version>0.5.7-incubating-SNAPSHOT</version>
   <name>Zeppelin: Lens interpreter</name>
   <url>http://www.apache.org</url>
   
diff --git a/markdown/pom.xml b/markdown/pom.xml
index 8f95162..0cb9c26 100644
--- a/markdown/pom.xml
+++ b/markdown/pom.xml
@@ -22,14 +22,14 @@
   <parent>
     <artifactId>zeppelin</artifactId>
     <groupId>org.apache.zeppelin</groupId>
-    <version>0.5.6-incubating</version>
+    <version>0.5.7-incubating-SNAPSHOT</version>
     <relativePath>..</relativePath>
   </parent>
 
   <groupId>org.apache.zeppelin</groupId>
   <artifactId>zeppelin-markdown</artifactId>
   <packaging>jar</packaging>
-  <version>0.5.6-incubating</version>
+  <version>0.5.7-incubating-SNAPSHOT</version>
   <name>Zeppelin: Markdown interpreter</name>
   <url>http://zeppelin.incubator.apache.org</url>
 
diff --git a/phoenix/pom.xml b/phoenix/pom.xml
index 9fa982f..79b225e 100644
--- a/phoenix/pom.xml
+++ b/phoenix/pom.xml
@@ -22,13 +22,13 @@
   <parent>
     <artifactId>zeppelin</artifactId>
     <groupId>org.apache.zeppelin</groupId>
-    <version>0.5.6-incubating</version>
+    <version>0.5.7-incubating-SNAPSHOT</version>
   </parent>
 
   <groupId>org.apache.zeppelin</groupId>
   <artifactId>zeppelin-phoenix</artifactId>
   <packaging>jar</packaging>
-  <version>0.5.6-incubating</version>
+  <version>0.5.7-incubating-SNAPSHOT</version>
   <name>Zeppelin: Apache Phoenix Interpreter</name>
   <description>Zeppelin interprter for Apache Phoenix</description>
   <url>http://zeppelin.incubator.apache.org</url>
diff --git a/pom.xml b/pom.xml
index 66e4438..c3f554f 100755
--- a/pom.xml
+++ b/pom.xml
@@ -34,7 +34,7 @@
   <groupId>org.apache.zeppelin</groupId>
   <artifactId>zeppelin</artifactId>
   <packaging>pom</packaging>
-  <version>0.5.6-incubating</version>
+  <version>0.5.7-incubating-SNAPSHOT</version>
   <name>Zeppelin</name>
   <description>Zeppelin project</description>
   <url>http://zeppelin.incubator.apache.org/</url>
@@ -57,7 +57,7 @@
     <url>https://git-wip-us.apache.org/repos/asf/incubator-zeppelin.git</url>
     <connection>scm:git:https://git-wip-us.apache.org/repos/asf/incubator-zeppelin.git</connection>
     <developerConnection>scm:git:https://git-wip-us.apache.org/repos/asf/incubator-zeppelin.git</developerConnection>
-    <tag>v0.5.6</tag>
+    <tag>HEAD</tag>
   </scm>
 
   <developers>
diff --git a/postgresql/pom.xml b/postgresql/pom.xml
index afe09ba..6c1bc94 100644
--- a/postgresql/pom.xml
+++ b/postgresql/pom.xml
@@ -22,13 +22,13 @@
   <parent>
     <artifactId>zeppelin</artifactId>
     <groupId>org.apache.zeppelin</groupId>
-    <version>0.5.6-incubating</version>
+    <version>0.5.7-incubating-SNAPSHOT</version>
   </parent>
 
   <groupId>org.apache.zeppelin</groupId>
   <artifactId>zeppelin-postgresql</artifactId>
   <packaging>jar</packaging>
-  <version>0.5.6-incubating</version>
+  <version>0.5.7-incubating-SNAPSHOT</version>
   <name>Zeppelin: PostgreSQL interpreter</name>
   <url>http://www.apache.org</url>
 
diff --git a/shell/pom.xml b/shell/pom.xml
index 49b89ab..a743649 100644
--- a/shell/pom.xml
+++ b/shell/pom.xml
@@ -22,14 +22,14 @@
   <parent>
     <artifactId>zeppelin</artifactId>
     <groupId>org.apache.zeppelin</groupId>
-    <version>0.5.6-incubating</version>
+    <version>0.5.7-incubating-SNAPSHOT</version>
     <relativePath>..</relativePath>
   </parent>
 
   <groupId>org.apache.zeppelin</groupId>
   <artifactId>zeppelin-shell</artifactId>
   <packaging>jar</packaging>
-  <version>0.5.6-incubating</version>
+  <version>0.5.7-incubating-SNAPSHOT</version>
   <name>Zeppelin: Shell interpreter</name>
   <url>http://zeppelin.incubator.apache.org</url>
 
diff --git a/spark-dependencies/pom.xml b/spark-dependencies/pom.xml
index 770f7e9..ccad5f5 100644
--- a/spark-dependencies/pom.xml
+++ b/spark-dependencies/pom.xml
@@ -22,14 +22,14 @@
   <parent>
     <artifactId>zeppelin</artifactId>
     <groupId>org.apache.zeppelin</groupId>
-    <version>0.5.6-incubating</version>
+    <version>0.5.7-incubating-SNAPSHOT</version>
     <relativePath>..</relativePath>
   </parent>
 
   <groupId>org.apache.zeppelin</groupId>
   <artifactId>zeppelin-spark-dependencies</artifactId>
   <packaging>jar</packaging>
-  <version>0.5.6-incubating</version>
+  <version>0.5.7-incubating-SNAPSHOT</version>
   <name>Zeppelin: Spark dependencies</name>
   <description>Zeppelin spark support</description>
   <url>http://zeppelin.incubator.apache.org</url>
diff --git a/spark/pom.xml b/spark/pom.xml
index bc37fde..a55bf5b 100644
--- a/spark/pom.xml
+++ b/spark/pom.xml
@@ -22,14 +22,14 @@
   <parent>
     <artifactId>zeppelin</artifactId>
     <groupId>org.apache.zeppelin</groupId>
-    <version>0.5.6-incubating</version>
+    <version>0.5.7-incubating-SNAPSHOT</version>
     <relativePath>..</relativePath>
   </parent>
 
   <groupId>org.apache.zeppelin</groupId>
   <artifactId>zeppelin-spark</artifactId>
   <packaging>jar</packaging>
-  <version>0.5.6-incubating</version>
+  <version>0.5.7-incubating-SNAPSHOT</version>
   <name>Zeppelin: Spark</name>
   <description>Zeppelin spark support</description>
   <url>http://zeppelin.incubator.apache.org</url>
diff --git a/tajo/pom.xml b/tajo/pom.xml
index 10bed77..1dba26d 100644
--- a/tajo/pom.xml
+++ b/tajo/pom.xml
@@ -21,14 +21,14 @@
   <parent>
     <artifactId>zeppelin</artifactId>
     <groupId>org.apache.zeppelin</groupId>
-    <version>0.5.6-incubating</version>
+    <version>0.5.7-incubating-SNAPSHOT</version>
     <relativePath>..</relativePath>
   </parent>
 
   <groupId>org.apache.zeppelin</groupId>
   <artifactId>zeppelin-tajo</artifactId>
   <packaging>jar</packaging>
-  <version>0.5.6-incubating</version>
+  <version>0.5.7-incubating-SNAPSHOT</version>
   <name>Zeppelin: Tajo interpreter</name>
   <url>http://www.apache.org</url>
 
diff --git a/zeppelin-distribution/pom.xml b/zeppelin-distribution/pom.xml
index b84a72f..4845b10 100644
--- a/zeppelin-distribution/pom.xml
+++ b/zeppelin-distribution/pom.xml
@@ -22,7 +22,7 @@
   <parent>
     <artifactId>zeppelin</artifactId>
     <groupId>org.apache.zeppelin</groupId>
-    <version>0.5.6-incubating</version>
+    <version>0.5.7-incubating-SNAPSHOT</version>
     <relativePath>..</relativePath>
   </parent>
 
diff --git a/zeppelin-interpreter/pom.xml b/zeppelin-interpreter/pom.xml
index 5ac6793..4030203 100644
--- a/zeppelin-interpreter/pom.xml
+++ b/zeppelin-interpreter/pom.xml
@@ -23,14 +23,14 @@
   <parent>
     <artifactId>zeppelin</artifactId>
     <groupId>org.apache.zeppelin</groupId>
-    <version>0.5.6-incubating</version>
+    <version>0.5.7-incubating-SNAPSHOT</version>
     <relativePath>..</relativePath>
   </parent>
 
   <groupId>org.apache.zeppelin</groupId>
   <artifactId>zeppelin-interpreter</artifactId>
   <packaging>jar</packaging>
-  <version>0.5.6-incubating</version>
+  <version>0.5.7-incubating-SNAPSHOT</version>
   <name>Zeppelin: Interpreter</name>
   <description>Zeppelin Interpreter</description>
   <url>http://zeppelin.incubator.apache.org</url>
diff --git a/zeppelin-server/pom.xml b/zeppelin-server/pom.xml
index 8162392..6c9c245 100644
--- a/zeppelin-server/pom.xml
+++ b/zeppelin-server/pom.xml
@@ -22,14 +22,14 @@
   <parent>
     <artifactId>zeppelin</artifactId>
     <groupId>org.apache.zeppelin</groupId>
-    <version>0.5.6-incubating</version>
+    <version>0.5.7-incubating-SNAPSHOT</version>
     <relativePath>..</relativePath>
   </parent>
 
   <groupId>org.apache.zeppelin</groupId>
   <artifactId>zeppelin-server</artifactId>
   <packaging>jar</packaging>
-  <version>0.5.6-incubating</version>
+  <version>0.5.7-incubating-SNAPSHOT</version>
   <name>Zeppelin: Server</name>
   <url>http://www.nflabs.com</url>
 
diff --git a/zeppelin-web/pom.xml b/zeppelin-web/pom.xml
index 124f859..86f10b4 100644
--- a/zeppelin-web/pom.xml
+++ b/zeppelin-web/pom.xml
@@ -22,14 +22,14 @@
   <parent>
     <artifactId>zeppelin</artifactId>
     <groupId>org.apache.zeppelin</groupId>
-    <version>0.5.6-incubating</version>
+    <version>0.5.7-incubating-SNAPSHOT</version>
     <relativePath>..</relativePath>
   </parent>
 
   <groupId>org.apache.zeppelin</groupId>
   <artifactId>zeppelin-web</artifactId>
   <packaging>war</packaging>
-  <version>0.5.6-incubating</version>
+  <version>0.5.7-incubating-SNAPSHOT</version>
   <name>Zeppelin: web Application</name>
 
   <!-- See https://github.com/eirslett/frontend-maven-plugin/issues/229 -->
diff --git a/zeppelin-zengine/pom.xml b/zeppelin-zengine/pom.xml
index 3f868f9..5c72609 100644
--- a/zeppelin-zengine/pom.xml
+++ b/zeppelin-zengine/pom.xml
@@ -23,14 +23,14 @@
   <parent>
     <artifactId>zeppelin</artifactId>
     <groupId>org.apache.zeppelin</groupId>
-    <version>0.5.6-incubating</version>
+    <version>0.5.7-incubating-SNAPSHOT</version>
     <relativePath>..</relativePath>
   </parent>
 
   <groupId>org.apache.zeppelin</groupId>
   <artifactId>zeppelin-zengine</artifactId>
   <packaging>jar</packaging>
-  <version>0.5.6-incubating</version>
+  <version>0.5.7-incubating-SNAPSHOT</version>
   <name>Zeppelin: Zengine</name>
   <description>Zeppelin Zengine</description>
   <url>http://zeppelin.incubator.apache.org</url>