CbqBridge Implementation

CbqBridge allow Cbq Engine to talk to indexing. This is only an interim
solution to allow easy testing.

Change-Id: I4b070ffff267a9ac615b49b02c0675faf7264d0c
Reviewed-on: http://review.couchbase.org/38748
Reviewed-by: John Liang <johliang00@gmail.com>
Reviewed-by: Deepkaran Salooja <deepkaran.couchbase@gmail.com>
Tested-by: Deepkaran Salooja <deepkaran.couchbase@gmail.com>