CBD-1412: split revAB into multiple modules

Change-Id: I0e8e0b4c96b64e919e1f83eeb852f4dc5e605d68
Reviewed-on: http://review.couchbase.org/39999
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Pavel Paulau <pavel.paulau@gmail.com>