Remove copyright headers

src/app/services/websocket.service.ts

@@ -1,6 +1,3 @@
-// Copyright (C) 2018 Avatao.com Innovative Learning Kft.
-// All Rights Reserved. See LICENSE file for details.
-
 import { Injectable } from '@angular/core';
 import { Observable } from 'rxjs';
 import { webSocket, WebSocketSubject } from 'rxjs/webSocket';