feat(event-manager): added method to register a list of listeners

frontend/src/lib/event-manager/event-manager.js

@@ -31,6 +31,10 @@ export class EventManager {
         this._registeredListeners.push(eventWrapper);
     }
 
+    registerListeners(eventWrappers) {
+        eventWrappers.forEach((eventWrapper) => this.registerNewListener(eventWrapper));
+    }
+
     registerNewMutationObserver(callback, domNode, config) {
         let observer = new MutationObserver(callback);
         observer.observe(domNode, config);