Holding keys doesn't work

[MulverineX]

Reproduce:

1. Move peripherals to client device
2. Press and hold any key

Expected: the key fires on the client once, then after a second it fires every 100ms

Actual: the key fires once and only once, pretty annoying for backspace.

It appears that KeyUp is being fired correctly, so my previous assertion that its a problem for games was incorrect.

[feschber]

What devices are you using on the sending / receiving end?

[MulverineX]

Same as #46

[feschber]

Okay so this is a Windows specific problem. The Windows Backend needs a bit of work.