Gamepad Emulation Support

[jawaff]

Add support for reactions that will emulate a gamepad's input.

[jawaff]

I'm looking into the possibility of using a C++ library that deals with DirectInput -- a lot of games are made with C++ anyway and probably mostly use DirectInput. The first library I've come across is Vjoy.

[jawaff]

http://vjoystick.sourceforge.net/site/

[jawaff]

The plan so far is to interface with the vjoy C++ library using Javacpp.

https://github.com/bytedeco/javacpp
http://vjoystick.sourceforge.net/site/

[jawaff]

We may need to figure something out for supporting gamepads on Linux. vjoystick is a Windows only library if I'm not mistaken.

[jawaff]

It's been a while, but I've gone back to figure out how to deal with Javacpp. I found a wiki page that has some information on how to use their parser to generate Java files. https://github.com/bytedeco/javacpp-presets/wiki/Create-New-Presets