allow clients to react to socket setup and auth message

currently, clients don't get notified when a socket is setup (or fails), or the auth check succeeds, or fails.

we need to add something to allow module code to hook into this.

possible implementation:

(function ($) {

Drupal.Nodejs.connectionSetupHandler.myModuleConfigCheck = {
  connectionFailure: function (message) {
  },
  connectionSuccess: function (message) {
  },
  authFailure: function (message) {
  },
  authSuccess: function (message) {
  }
};

})(jQuery);