Cleanups

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/project-release-tools/trunk@1553653 13f79535-47bb-0310-9956-ffa450edef68
Added svnmucc like utility method for bulk SVN operations; added release dist promotion task

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/project-release-tools/trunk@1553654 13f79535-47bb-0310-9956-ffa450edef68