Evaluate implementation of Proactor test for End-to-End testing

[evilaliv3]

While working on GlobaLeaks, we found out that It would be valuable to implement a simple end2end testing of the library by means of Protractor that enable testing of AngularJS applications.

given the fact that angular-relative-date is using Grunt, this would be really simple by using grunt-protractor-runner and would require simple writing some protractor tests of angular-relative-date.

@mapmeld @siddii