Kibana plugin status listeners should execute callback immediately when listener matches current state

[simianhacker]

When a listener is attached to a plugin's status for a color event and the plugin's current state is the same as the color event, the listener should be executed immediately.

server.plugin.elasticsearch.status.green("Kibana ready");
server.plugin.elasticsearch.status.on('green', function () {
  // Will never get called if the elasticsearch plugin never changes
  // status from green to red and back again.
});