code: function(eventName, selector, callback) {
          if (!isString(selector)) {
              callback = selector;
              selector = '';
          }
  
          if (callback) {
              var events = this.events[eventName];
              if (events) {
                  events = events[selector];
                  if (events) {
                      for (var i = 0; i < events.length; i++) {
                          if (events[i] === callback) {
                              events.splice(i, 1);
                              i--;
                          }
                      }
                  }
              }
          } else {
              this.events[eventName][selector] = [];
          }
      }
docs: Stops listening to an event.
  
  The arguments are the same as for on(), but when no callback is given, all callbacks for the
  given event and class are discarded.