test fix for SOLR-4935, path separator issue (second)

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1495661 13f79535-47bb-0310-9956-ffa450edef68
SOLR-4942: test improvements to randomize use of compound files

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1495668 13f79535-47bb-0310-9956-ffa450edef68
fix for LUCENE-4890

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1495757 13f79535-47bb-0310-9956-ffa450edef68
adding LUCENE-4890 fix to trunk/lucene/CHANGES.txt

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1495764 13f79535-47bb-0310-9956-ffa450edef68