Fix style issues in production.js config
Update protractor and add grunt task
Use minified sortable.js in production
Set up protractor with phantomjs

Note: need grunt-phantom to start phantomjs, because protractor (or
selenium) seems unable to start phantomjs
(https://github.com/angular/protractor/blob/239ba96a816a59aa6f8371fcd7306f91c7d03882/docs/browser-setup.md#setting-up-phantomjs
did not work)