Request spec time feature

Had to fiddle with text field form component to allow it to have a class attribute assigned from form view;
I started with client-side, by adding a modal and handling the time duration update.
It's not finished of course, just wanted to get feedback whether I'm going in the right direction with this.

Also a note: using simple_form gem will greatly simplify forms and will generate proper html (for example, the ids of inputs now have this: 'request[duration]', which is a no-no. Although works in HTML, jQuery fails with this kind of selector.