Set version to 0.6.0-SNAPSHOT

Author: felixbarny

pom.xml

@@ -5,7 +5,7 @@
     <groupId>co.elastic.apm</groupId>
     <artifactId>apm-agent-parent</artifactId>
     <name>${project.groupId}:${project.artifactId}</name>
-    <version>0.5.2-SNAPSHOT</version>
+    <version>0.6.0-SNAPSHOT</version>
     <packaging>pom</packaging>
     <inceptionYear>2018</inceptionYear>
     <organization>