SLING-3191 : Prevent endless recursion of composite health checks

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1533742 13f79535-47bb-0310-9956-ffa450edef68
SLING-3192 : Correct metatype information for health checks

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1533746 13f79535-47bb-0310-9956-ffa450edef68