FTS - Extending the search request for collections

 A search request would now carry additional scope and collection id/name information. cbft will internally map this query to a conjunction within which the first query would be the query as requested by the user, and second query will be a match over scope_collection against the the $scope$collection field within the index. Bleve should not be affected at all with these changes.

REST/gRPC endpoints to accept scope name and collection name. CBFT will then need to concatenate the scope and collection name and add in conjunction to the requested search a match on the _scope_collection field.