Begin implementing api-connection

Add HttpClient to AuthenticationService
Send request to arsnova backend to gain JWT token for guest user

src/app/authentication.service.ts

@@ -92,13 +92,4 @@ export class AuthenticationService {
     return this.user.token;
   }
 
-  setToken(token?: string): boolean {
-    // Initial check for token
-    if (!token) {
-      token = this.getToken();
-      return true;
-    }
-
-    return true;
-  }
 }

src/app/user.ts

@@ -2,14 +2,14 @@ import { AuthProvider } from './auth-provider';
 import { UserRole } from './user-roles.enum';
 
 export class User {
-  userId: string;
+  id: string;
   loginId: string;
   authProvider: AuthProvider;
   token: string;
   userRole: UserRole;
 
-  constructor(userId: string, loginId: string, authProvider: AuthProvider, token: string, userRole: UserRole) {
-    this.userId = userId;
+  constructor(id: string, loginId: string, authProvider: AuthProvider, token: string, userRole: UserRole) {
+    this.id = id;
     this.loginId = loginId;
     this.authProvider = authProvider;
     this.token = token;