Merged revision(s) 1468638 from lucene/dev/branches/branch_4x:
LUCENE-4937: Fix incorrect sorting of float/double values (+/-0, NaN).

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1468640 13f79535-47bb-0310-9956-ffa450edef68