SLING-7418 Use bnd Maven plugins

fix optional package imports
diff --git a/bnd.bnd b/bnd.bnd
index 3be85ce..a69d7f5 100644
--- a/bnd.bnd
+++ b/bnd.bnd
@@ -10,9 +10,16 @@
 
 DynamicImport-Package:\
   javax.servlet,\
-  javax.servlet.http;version="[2.3,3)",\
-  org.apache.commons.io.output;version="[2.4.0,3)",\
-  org.apache.felix.inventory;version="[1.0.0,2)"
+  javax.servlet.http,\
+  org.apache.commons.io.output,\
+  org.apache.felix.inventory
+
+Import-Package:\
+  javax.servlet;resolution:=optional,\
+  javax.servlet.http;resolution:=optional,\
+  org.apache.commons.io.output;resolution:=optional,\
+  org.apache.felix.inventory;resolution:=optional,\
+  *
 
 Provide-Capability:\
   osgi.service;objectClass=com.codahale.metrics.MetricRegistry,\