Changes:
- (Big Picture) Improved back behavior throughout the UI
- (Big Picture) Improved movie streaming and loading UI
- (Big Picture) Fixed navigating to DLC and guides in the library
- (Big Picture) Fixed movie playback intermittently failing when quickly navigating Trailer TV
- (Big Picture) Changed store search to search for partial application names
- (Big Picture) Added discount timers and other UI to store
- (Linux) Fixed excessive Steam cpu use when running Team Fortress 2
- (Linux) Fixed overlay crash when starting Cubemen