Don't force a requirement on jquery-rails, as there are other valid modes of inclusion which eschew it.

We use the [conditional comment trick](http://blog.jquery.com/2013/03/01/jquery-2-0-beta-2-released/) to include jquery. As such, we don't rely on `require jquery` via jquery-rails, and in fact using that statement causes our app to break because it would load a second copy of jquery which overwrites the first, which had already been extended with jquery_ujs.

We'd like to remove jquery-rails while still using jquery-ui-rails, but you guys place a hard dependency on it. Doesn't seem necessary to me, could you reconsider?