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