SOLR-5463: more details in case of spooky 'walk already seen' errors

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1558939 13f79535-47bb-0310-9956-ffa450edef68
SOLR-4260: ConcurrentUpdateSolrServer#blockUntilFinished can return before all previously added updates have finished. This could cause distributed updates meant for replicas to be lost.

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1558978 13f79535-47bb-0310-9956-ffa450edef68
SOLR-4260: Add name to CHANGES

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1558980 13f79535-47bb-0310-9956-ffa450edef68
SOLR-4260: Guard against NPE.

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1558985 13f79535-47bb-0310-9956-ffa450edef68
SOLR-4260: If in blockUntilFinished and there are no Runners running and the queue is not empty, start a new Runner.

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1558996 13f79535-47bb-0310-9956-ffa450edef68
SOLR-5476: Fix forbidden.

PLEASE RUN "ant precommit" (root) or alternatively the faster "ant check-forbidden-apis" (in your module folder) before committing!

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1559043 13f79535-47bb-0310-9956-ffa450edef68
improve javadocs/comments

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1559086 13f79535-47bb-0310-9956-ffa450edef68
 SOLR-5476 logging added

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1559100 13f79535-47bb-0310-9956-ffa450edef68
improve javadocs

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1559103 13f79535-47bb-0310-9956-ffa450edef68
Merge branch 'trunk' into efbytesref