add javadoc

git-svn-id: https://svn.apache.org/repos/asf/archiva/trunk@1547295 13f79535-47bb-0310-9956-ffa450edef68
continue moving maven logic out of dav module

git-svn-id: https://svn.apache.org/repos/asf/archiva/trunk@1547296 13f79535-47bb-0310-9956-ffa450edef68