track rebalance progress even if it's not running
track rebalance progress even if it's not running

Change-Id: I3cd5c2a58b3aa1c27c19f1907a798c96f2925e87
Reviewed-on: http://review.couchbase.org/25204
Tested-by: buildbot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>
Reviewed-by: Pavel Paulau <dd88eded64e90046a680e3a6c0828ceb8fe8a0e7@gmail.com>

couchbase/cbmonitor,vmx/cbagent,couchbase/cbagent,couchbase/cbmonitor,mikewied/cbagent,pavel-paulau/cbagent