Allow defining all possible full text indexes.

[ #2924 ]
Adding skeletion contextual text search
Set text search language
Set text search field projections
Text search raw execute
Adding in each specs
Add specs around stats
Move selecting into command module
Hook text search into mongo context.

[ #2924 ]
Hook text search into criteria.

[ #2924 ]
Hook text search into Findable

[ #2924 ]
Update changelog for text search feature.

[ close #2924 ]