fix(@angular/cli): allow e2e multi capabilities

Thanks to @raymondkarstensen for this solution.

Fix #975

Author: filipesilva

packages/@angular/cli/blueprints/ng/files/protractor.conf.js

@@ -19,12 +19,10 @@ exports.config = {
     defaultTimeoutInterval: 30000,
     print: function() {}
   },
-  beforeLaunch: function() {
+  onPrepare() {
     require('ts-node').register({
       project: 'e2e/tsconfig.e2e.json'
     });
-  },
-  onPrepare() {
     jasmine.getEnv().addReporter(new SpecReporter({ spec: { displayStacktrace: true } }));
   }
 };