Fix: Do not check in dependencies, run install on Travis

This PR

* [x] removes dependencies installed with bower
* [x] adds `bower_components` to `.gitignore`
* [x] updates `.travis.yml` to explicitly install dependencies (`install` section), run tests (`script` section)
* [x] requires `bower` as a dependency
* [x] installs [`jasmine`](https://github.com/jasmine/jasmine)