SLING-3651 : buglet fix introduced by SLING-3651 : result of getSyncDirectoryFile must be an absolute file, thus use the project.getLocation().toFile() - otherwise it ends up as relative file to the eclipse app start directory

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1603462 13f79535-47bb-0310-9956-ffa450edef68