MB-11324: disable collect button if no selected nodes
MB-11324: disable collect button if no selected nodes

Change-Id: I7462969e2d8280c0c4fc26760417c74920bc5c5c
Reviewed-on: http://review.couchbase.org/38008
Reviewed-by: Aliaksey Kandratsenka <340b8e09ca65cd3fc686427fcfed17e87eaf61e2@gmail.com>
Tested-by: Aliaksey Kandratsenka <340b8e09ca65cd3fc686427fcfed17e87eaf61e2@gmail.com>

nimishzynga/ns_server,nimishzynga/ns_server,nimishzynga/ns_server,membase/ns_server,ceejatec/ns_server,nimishzynga/ns_server,ceejatec/ns_server,mschoch/ns_server,t3rm1n4l/ns_server,membase/ns_server,t3rm1n4l/ns_server,nimishzynga/ns_server,ceejatec/ns_server,t3rm1n4l/ns_server,mschoch/ns_server,t3rm1n4l/ns_server,mschoch/ns_server,ceejatec/ns_server,membase/ns_server,membase/ns_server,ceejatec/ns_server,mschoch/ns_server,membase/ns_server,ceejatec/ns_server,membase/ns_server,mschoch/ns_server,nimishzynga/ns_server,t3rm1n4l/ns_server,mschoch/ns_server