Expose recursion level for Hunspell token filter. Closes #3369
Generate consistent random settings across nodes

IndexGatewayTests rely on that all nodes have the same type of
storage to pass consistently. Random configs should be the same for all
nodes in the cluster.
Fix CustomScoreSearchTest that assumed a certain order of doc IDs with equal score
Add facility to index in random order

Tests are more reproducible if documents are indexed in random order
with random flushes/refreshes etc. in order to catch corner cases
where doc Ids are used for tie-breaking and tests rely on a certain
order.
Fixed hang when submitting mappings and no changes are made

Added missing listener call before return

Closes #3381
Can't share XContentBuilder across threads.
break out if there no more liveIds. This can happen if another thread emptied the liveIds.
Added regression tests for #3381
0.90.3 uses lucene 44
Math is as hard as Concurrency
fix test to use correct store setting
Added prefix suggestions based on AnalyzingSuggester

This commit introduces near realtime suggestions. For more information about
its usage refer to github issue #TODO

From the implementation point of view, a custom AnalyzingSuggester is used
in combination with a custom postingsformat (which is not exposed to the user
anywhere for him to use).