glusterd: Differentiate rebalance status and remove-brick status messages

previously when user triggred 'gluster volume remove-brick VOLNAME
BRICK start' then command' gluster volume rebalance <volname> status'
showing output even user has not triggred "rebalance start" and when
user triggred 'gluster volume rebalance <volname> start' then command
'gluster volume remove-brick VOLNAME BRICK status' showing output even
user has not run rebalance start and remove brick start.

regression test failed in previous patch. file test/dht.rc and
test/bug/bug-973073 edited to avoid regression test failure.

now with this fix it will differentiate rebalance and remove-brick
status messages.

Signed-off-by: ggarg <ggarg@redhat.com>

Change-Id: I7f92ad247863b9f5fbc0887cc2ead07754bcfb4f
BUG: 1089668
Reviewed-on: http://review.gluster.org/7517
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Atin Mukherjee <amukherj@redhat.com>
Reviewed-by: Humble Devassy Chirammal <humble.devassy@gmail.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>