LUCENE-5757: move RamUsageEstimator reflector to test-framework

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_4x@1602526 13f79535-47bb-0310-9956-ffa450edef68
SOLR-5426: Fixed a bug in ReverseWildCardFilter that could cause InvalidTokenOffsetsException when highlighting (merge r1602525)

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_4x@1602527 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5760: Speed up BufferedIndexInput.randomAccessSlice

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_4x@1602531 13f79535-47bb-0310-9956-ffa450edef68