Coordinator/IndexManager M5 checkin

- Topology Maintenance
- Handling message from projector
- Stability timestamp generation

CBIDXT-226
CBIDXT-161
CBIDXT-162
CBIDXT-163
CBIDXT-157
CBIDXT-158
CBIDXT-180

Change-Id: I1c4192d48b132e076f95c7f98d48bc630b8f1737
Reviewed-on: http://review.couchbase.org/42487
Reviewed-by: John Liang <johliang00@gmail.com>
Tested-by: John Liang <johliang00@gmail.com>