Pagination with Infinite Scrolling

I have implemented the Pagination Features along with Infinite Scrolling. I also have changed the travis.yml file to enable firefox on travis to run selenium tests.

Included is also the change to remove the heroku deployment error and the bootstrap popover error and also some improvements to the styling of the front page.

I have also added the jquery-ui library so that my infinte scrolling library would work but that didn't require any further gems or file downloads since it was bundled with the `jquery-rails` gem.

Also, to use selenium on your machine, be sure to run `selenium install` to install selenium on your machine.