Add a resolution field and improve general --list-formats output
Add temporary _sort_formats helper function
Add more tests for format selection
[youtube] Simplify format specification
[dreisat] Use centralized format sorting
[mit] Add support for multiple formats
[spiegel] Use centralized sorting
[zdf] Use centralized sorting
[mdr] Use centralized format selection
[yahoo] Use centralized sorting, and add tbr field
[wistia] Use centralized sorting
[appletrailers] Use centralized format selection
Merge remote-tracking branch 'origin/master'