Updates design to match new `osu-web` design. Adds TestCase for visual testing.
This also - Renames TextAwesome to SpriteIcon. - Removes the default size of "20" from SpriteIcon (now defaults to the underlying texture size).
Most issues were related to BeginLoopedSequence usage and lack of "this." in front of transform helpers.
- Supersedes https://github.com/ppy/osu/pull/926. - [ ] Depends on https://github.com/ppy/osu-framework/pull/817.