LUCENE-5511: "ant precommit" / "ant check-svn-working-copy" now work again with any working copy format (thanks to svnkit 1.8.4).

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1575714 13f79535-47bb-0310-9956-ffa450edef68