Switch to parent pom 26

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1722720 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/pom.xml b/pom.xml
index 27197ea..7d5a24f 100644
--- a/pom.xml
+++ b/pom.xml
@@ -25,7 +25,7 @@
   <parent>
     <groupId>org.apache.sling</groupId>
     <artifactId>sling</artifactId>
-    <version>25</version>
+    <version>26</version>
     <relativePath/>
   </parent>