Add a field data based TermsFilter

Add FieldDataTermsFilter that compares terms out of
the fielddata cache. When filtering on a large
set of terms this filter can be considerably faster
than using a standard lucene terms filter.

Add the "fielddata" execution mode to the
terms filter parser to enable the use of
the new FieldDataTermsFilter.

Add supporting tests and documentation.

Closes #4209
Running the node stats api while a shard is moving onto the node logs an exception
fixes #4203
build randomization script

this script genereates envrionment property file necessary to do
jenkins randomization testing
jenkin hookup modification

1) add build_desc property variable
2) use build_id plus build_number as an unique file name
3) tools subdirectory should be under current PWD when the script is
executing
NPE in PluginsService when starting elasticsearch with a wrong user
When starting elasticsearch with a wrong linux user, it could generate a `NullPointerException` when `PluginsService` tries to list available plugins in `./plugins` dir.

To reproduce:

* create a plugins directory with `rwx` rights for root user only
* launch elasticsearch from another account (elasticsearch for example)

Related discussion: https://groups.google.com/forum/#!topic/elasticsearch/_WRW4Qfpo7M

Closes #4186.
Closes #4187.
Removed redundant masterNodeTimeout, already present in the ClusterStateUpdateRequest base class
Refactored open/close index api to make use of the new recently introduced generic ack mechanism

Closes #4169
Added base ClusterStateUpdateRequest class that executes on multiple indices
Added readTimeout, writeTimeout, readAcknowledged and writeAcknowledged methods variation without version as parameter, to be used by api that always read and write those parameters. Helps avoiding to call the variation that accepts a Version with actual version null.
Refactoring IndicesAnalysisService

Using enums where possible in order to clean up the code in IndicesAnalysisService

Also introduced a simpler generic caching mechanism, and tests.
Use #assertAcked() for verification.
Squashed old stuff :D
Start using RamAccountingTermsEnum
no need to create a new breaker on shutdown
Add test for RamAccountingTermsEnum
Add breaker stats to _node/stats, with all the fixins
remove unneeded logging
better instantiating of MemoryAggregatingCircuitBreaker
Adjust circuit breaker after actual data is loaded, much more accurate now
Pass CircuitBreakerService instead of the breaker, allowing for updates