Start to fix things

* [x] Add gulp task to run e2e tests
* [ ] Download webdriver on install instead of npm test
* [ ] Fix sync error, tests not waiting for app to be ready
File download by webdriver update was corrupt.
Got another one with : 

```
curl http://selenium-release.storage.googleapis.com/2.42/selenium-server-standalone-2.42.2.jar -o node_modules/protractor/selenium/selenium-server-standalone-2.42.2.jar
```