Added alias action validation

Moved alias action validation to IndicesAliasesRequest, so that Java api and RestIndexPutAliasAction can benefit from it too.
Added check in MetaDataIndexAliasesService too.

Closes #3363
Cluster State Update APIs (master node) to respect master_timeout better
Currently, the master node might be processing too many cluster state events, and then be blocked on waiting for its respective even to be processed. We can use the new cluster state update timeout support to use the master_timeout value and respect it.

closes #3365
Cluster State Update APIs (master node) to respect master_timeout better
Currently, the master node might be processing too many cluster state events, and then be blocked on waiting for its respective even to be processed. We can use the new cluster state update timeout support to use the master_timeout value and respect it.

closes #3365
Cluster State Update APIs (master node) to respect master_timeout better
also respect the timeout when trying to obtain the md lock
relates #3365
should be 500...
Add FastVectorHighlighter support for more complex queries.

FastVectorHighlighter fails at highlighting some complex queries such as
multi phrase queries which have two terms at the same position. This can be
easily triggered by running a `match_phrase` query with an analyzer which
outputs synonyms such as SynonymFilter or WordDelimiterFilter.

Close #3357
move master actions to accept a lister, improve cluster service state execution
- master actions many times end up being executed on the cluster service, so there is no need to block them on the management thread pool to wait for a response, this remove the load on the management thread pool, and also simplifies the code implementing it
- cluster service state update exception handling was improved to include a callback when a failure happens during state update execution, this makes sure that we catch all relevant exceptions and invoke the callback, as well as simplify the code of cluster state update tasks, as they can throw failures from within the execute method and then handle them properly
move master actions to accept a lister, improve cluster service state execution
- master actions many times end up being executed on the cluster service, so there is no need to block them on the management thread pool to wait for a response, this remove the load on the management thread pool, and also simplifies the code implementing it
- cluster service state update exception handling was improved to include a callback when a failure happens during state update execution, this makes sure that we catch all relevant exceptions and invoke the callback, as well as simplify the code of cluster state update tasks, as they can throw failures from within the execute method and then handle them properly
Add optimize thread pool (size 1) dedicated to perform explicit optimize API
Have a dedicated thread pool for explicit optimize calls (shard level optimize operations). By default, the size should be 1 to work the same with how things work currently allowing for only 1 shard level optimize on a node.

The change allows to see the optimize thread pool stats now, and potentially increase the thread pool size for beefy machines.

closes #3366
Upgrade to Lucene 4.4
Removed XPatternCaptureGroupTokenFilter
Added cluster pending tasks api.
Closes #3368
remove cached stream output
start to build the infra for simpler migration to netty 4, starting with removing the cache stream output handling as it will come built in
remove cached stream output
start to build the infra for simpler migration to netty 4, starting with removing the cache stream output handling as it will come built in
bulk refresh and update mapping cluster events
try and bulk as much as possible refresh and update mapping events, so they will all be processed at a single go, resulting in less cluster change events, and also reduce the load of multiple changes to the same index
also, change the prio for those to HIGH, since we want URGENT ones (like create index, delete index) to execute
better logging on failure to create index
if the index already exists, trace log it, since it might happen as a result of multiple index requests at the same time creating the index, all other ones, should be debug and not warn in the same spirit of other APIs
FuzzyLikeThisFieldQueryBuilder now defaults failOnUnsupportedField to true, to be consistent with REST API.

Closes #3374
don't xcontent locale if its ROOT for date since its the default
We should wait until the first blocking task is actual being executed.
The pending tasks can be returned out of order.
Cut over to JUnit & Randomized Runner from TestNG

For better integration with the Lucene Test Framework and the
availabilty of RandomizedRunner / Randommized Testing this commit
moves over from TestNG to JUnit.
This commit also moves relevant places over to RandomzedRunner for
reproduceability and removes copied classes from the Lucene Test
Framework.