LUCENE-5969: fail precommit on typo'ed TODO

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/lucene5969@1633451 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5969: fix TOODs and add missing license header

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/lucene5969@1633453 13f79535-47bb-0310-9956-ffa450edef68