Sort results in questions view

*Refers to https://www.pivotaltracker.com/story/show/49284103.*

## Sorting
Results my be sorted by:
- Score
- Activity (Newest/Oldest)
- Created (Newest/Oldest)

More categories may be discussed.

## Invocation
The sort screen is invoked by dragging the searchbar to the right or clicking on the button

## Tasks
- [ ] Build sort view
- [x] Create scroll view
- [x] Scroll on button press
- [ ] Scroll on user scrolling
- [ ] Sorting
- [ ] Sort results
- [ ] Hookup sorting with view