chore(karma): update Ionic imports

Closes https://github.com/driftyco/ionic/issues/5566.

ionic/util/test/util.spec.ts

@@ -1,4 +1,4 @@
-import * as util from '../../../ionic/util';
+import * as util from 'ionic-angular/util';
 
 export function run() {
   describe('extend', function() {

scripts/karma/system.config.js

@@ -1,6 +1,10 @@
 System.config({
   map: {
-    angular2: '/base/angular2',
-    ionic: '/base/ionic'
+    'angular2': '/base/angular2'
+  },
+  packages: {
+    'ionic-angular': {
+      main: 'index'
+    }
   }
 });