Use latest launchpad plugin

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1476893 13f79535-47bb-0310-9956-ffa450edef68
SLING-2829 : Correctly handle first run of background loader

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1476894 13f79535-47bb-0310-9956-ffa450edef68