SOLR-3622, SOLR-5847, SOLR-6194, SOLR-6269: Several DIH fixes/improvements

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1613406 13f79535-47bb-0310-9956-ffa450edef68
SOLR-6269

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1613619 13f79535-47bb-0310-9956-ffa450edef68
tests: null out static

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1613652 13f79535-47bb-0310-9956-ffa450edef68
SOLR-6231: Increased timeouts and hardened the RollingRestartTest

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1613834 13f79535-47bb-0310-9956-ffa450edef68
SOLR-6286: Add logging on how long we slept and how many docs were found

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1613838 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5850: use correct version comparator (at the moment) for versions in index segments, otherwise this logic will do the wrong thing on the next bugfix release!

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1613988 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5593: speed up javadocs generation in build

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1614058 13f79535-47bb-0310-9956-ffa450edef68
SOLR-6264: Distributed commit and optimize are executed serially across all replicas.

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1614118 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5850: fix smoke tester to verify the index's segment versions in fact match the version being tested

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1614149 13f79535-47bb-0310-9956-ffa450edef68
SOLR-6290: Harden and speed up CollectionsAPIAsyncDistributedZkTest

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1614194 13f79535-47bb-0310-9956-ffa450edef68
SOLR-6261: Run ZooKeeper watch event callbacks in parallel to the ZooKeeper event thread.

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1614244 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5852: log errors that occur during cleanupOldIndexFiles

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1614264 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5811, LUCENE-5788: Fix uninvertingreader to strictly follow dv api contract

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1614316 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5849: try to stress slicing better in BaseDirectoryTestCase

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1614339 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5483: IndexWriter now enforces max docs in one index

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1614388 13f79535-47bb-0310-9956-ffa450edef68
SOLR-6020: Auto-generate a unique key in schema-less example if data does not have an id field

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1614416 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5843: this is a bug not a feature!

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1614422 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5843: woops, I committed too much

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1614423 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5843: this is a bug not a feature!

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1614424 13f79535-47bb-0310-9956-ffa450edef68
SOLR-6020: Fix broken JavaDoc found by precommit.

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1614498 13f79535-47bb-0310-9956-ffa450edef68