merge in 4.8.1 CHANGES.txt

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1595869 13f79535-47bb-0310-9956-ffa450edef68
merge in 4.8.1 CHANGES.txt

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1595872 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5682: NPE in QueryRescorer when Scorer is null

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1595973 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5686: fail if LUCENE/SOLR_NNNN (_ instead of -) appears in changes

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woops, revert

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LUCENE-5686: fail if LUCENE/SOLR_NNNN (_ instead of -) appears in changes

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1596044 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5678: Use FileOutputStream instead of RandomAccessFile to write index data. BufferedIndexOutput and related APIs were removed.

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1596057 13f79535-47bb-0310-9956-ffa450edef68
SOLR-5681: Make the OverseerCollectionProcessor multi-threaded

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1596089 13f79535-47bb-0310-9956-ffa450edef68
SOLR-5468: report replication factor that was achieved for an update request if requested by the client application.

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1596092 13f79535-47bb-0310-9956-ffa450edef68
SOLR-5495: Raise the amount of time the test waits for replicas to become active after partitions are healed (to address intermittent Jenkins failures)

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1596103 13f79535-47bb-0310-9956-ffa450edef68
SOLR-5468: Add wait loop to see replicas become active after restoring partitions; to address intermittent Jenkins test failures.

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1596234 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5679: remove the single-parameter deleteDocuments() versions, in favor of the vararg ones

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1596296 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5679: leftover jdoc fix

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1596304 13f79535-47bb-0310-9956-ffa450edef68
SOLR-5495: Re-arrange location of SOLR-5495 and SOLR-5468 in CHANGES.txt

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1596315 13f79535-47bb-0310-9956-ffa450edef68
make this assert more robust

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1596346 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5670: add skip/FinalOutput to FST Outputs

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1596369 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5691: DocTermOrds lookupTerm is wrong in some cases

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1596370 13f79535-47bb-0310-9956-ffa450edef68
Update some build tools

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1596425 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5666: Fix idea project files

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1596429 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5650: applying Ryan's DIH patch.

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/lucene5650@1596472 13f79535-47bb-0310-9956-ffa450edef68