Replace middleman by Gulp

* Remove Middleman
* Add Gulp
* Scope JS with commonJS
* Remove Angular dependencies in tests
Because it's not used anymore. Default value was true and commented. I did some hack in the file to know if I was on CI or on development and so set the `singleRun` in consequence.
Now I've to run two different Gulp tasks:

* gulp tests => singleRun true (like CI)
* gulp tdd => singleRun false (for development)