[TEST] use length-norm as the tie-breaker in BlendedTermQueryTest
[DOC] Fixed flags example incorrect syntax
Upgrade to Lucene 4.7.1

 * Removed XTermsFilter fixed in LUCENE-5502
 * Switched back to automaton queries that caused failures due to LUCENE-5532
 * Fixed Highlight test that has different results due to LUCENE-5538