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
- [x] *Build sort view*
- [x] Create scroll view
- [x] Scroll on button press
- [x] Scroll on user scrolling
- [ ] Change sort order
- [x] Refine Interface
- [x] *Sorting*
- [x] Sort results are sorted by criterions
- [x] Hookup sorting with view
- [x] Sort initial view aswell