5.4 Released - Steam Controller support, better controller navigation

I updated the game to handle the new Steam Controllers that will be coming out soon! These have a right-side trackpad that emulates mouse input, giving you high-precision aiming and much greater control over your rotation speed vs. a traditional joystick. Plus there are grip buttons that give you easier access to the boost and jump commands (or whatever you want to map them to).

I also replaced my controller plugin with InControl, which means the game will support almost any controller / system combination under the sun.

In addition, I greatly improved menu navigation when using a controller. It had been pretty painful before, but now should be very easy and intuitive.

Also:
- Fixed weak jetpack in Air Raid
- Fixed Power Slide not being rebindable