CBQE-1105: add P1 rebalance progress cases

Change-Id: I4fb55b96112141510609244f4773595c99d727cd
Reviewed-on: http://review.couchbase.org/26157
Reviewed-by: Sangharsh Agarwal <sangharsh.agarwal@globallogic.com>
Tested-by: Sangharsh Agarwal <sangharsh.agarwal@globallogic.com>