LUCENE-5447: StandardTokenizer should break at consecutive chars matching Word_Break = MidLetter, MidNum and/or MidNumLet (merged trunk r1569586)

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_4x@1569601 13f79535-47bb-0310-9956-ffa450edef68