MB-5308: handle not ready buckets list in replications
MB-5308: handle not ready buckets list in replications

Fixes UI bug when buckets list was empty when in fact there were
buckets defined.

Change-Id: I23e31bec956ffa2d1ffbd0927bf2a310d68acf8c
Reviewed-on: http://review.couchbase.org/18883
Reviewed-by: Aliaksey Kandratsenka <340b8e09ca65cd3fc686427fcfed17e87eaf61e2@gmail.com>
Tested-by: Aliaksey Kandratsenka <340b8e09ca65cd3fc686427fcfed17e87eaf61e2@gmail.com>

membase/ns_server,nimishzynga/ns_server,pavel-blagodov/ns_server,daverigby/ns_server,t3rm1n4l/ns_server,ceejatec/ns_server,mschoch/ns_server,membase/ns_server,daverigby/ns_server,vzasade/ns_server,pavel-blagodov/ns_server,nimishzynga/ns_server,membase/ns_server,t3rm1n4l/ns_server,ceejatec/ns_server,t3rm1n4l/ns_server,mschoch/ns_server,pavel-blagodov/ns_server,vzasade/ns_server,ceejatec/ns_server,mschoch/ns_server,ceejatec/ns_server,nimishzynga/ns_server,t3rm1n4l/ns_server,pavel-blagodov/ns_server,daverigby/ns_server,ceejatec/ns_server,membase/ns_server,nimishzynga/ns_server,vzasade/ns_server,t3rm1n4l/ns_server,vzasade/ns_server,ceejatec/ns_server,nimishzynga/ns_server,mschoch/ns_server,daverigby/ns_server,membase/ns_server,membase/ns_server,nimishzynga/ns_server,daverigby/ns_server,mschoch/ns_server,mschoch/ns_server