add and rebalancing a node fails in the first attempt in 2.0 ({gen_fsm,sync_send_event,2}, {menelaus_web,do_handle_rebalance,3}

1) Create a 3 node cluster
2) Select any one of them as master
3) Add other nodes to this master
4) Rebalance.

From the AdminLog:-
Server error during processing: ["web request failed",
{path,"/controller/rebalance"},
{type,exit},
{what,
{noproc,
{gen_fsm,sync_send_event,
[{global,ns_orchestrator},
{start_rebalance,
['ns_1@10.1.6.39','ns_1@10.1.6.38',
'ns_1@10.1.6.40'],
[],[]}]}}},
{trace,
[{gen_fsm,sync_send_event,2},
{menelaus_web,do_handle_rebalance,3},
{menelaus_web,loop,3},
{mochiweb_http,headers,5},


From the diagnostic report.

                      [{registered_name,[]},
                       {status,waiting},
                       {initial_call,{proc_lib,init_p,5}},
                       {backtrace,
                        [<<"Program counter: 0x03dd4aa8 (gen_fsm:loop/7 + 152)">>,
                         <<"CP: 0x00000000 (invalid)">>,<<"arity = 0">>,<<>>,
                         <<"0x0473468c Return addr 0x01595750 (proc_lib:init_p_do_apply/3 + 28)">>,
                         <<"y(0) []">>,<<"y(1) infinity">>,
                         <<"y(2) mc_daemon">>,
                         <<"(3) {state,<<7 bytes>>,true,0,nil,[],100,undefined,0,8,<0.3723.1>,nil,[],#Port<0.14666">>,
                         <<"y(4) processing">>,<<"y(5) <0.3722.1>">>,
                         <<"y(6) <0.3721.1>">>,<<>>,
                         <<"0x047346ac Return addr 0x01223c44 (<terminate process normally>)">>,
                         <<"y(0) Catch 0x01595760 (proc_lib:init_p_do_apply/3 + 44)">>,
                         <<>>]},