[maven-release-plugin] prepare release org.apache.sling.engine-2.2.10

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1530208 13f79535-47bb-0310-9956-ffa450edef68
[maven-release-plugin] prepare for next development iteration

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1530210 13f79535-47bb-0310-9956-ffa450edef68