USB HID support

[blitz]

Relying on USB legacy emulation has various issues (see #8). We need USB HID support to have reliable input.

[udosteinberg]

There are some chipsets already out there where USB legacy support is no longer present. See for example issue 5 in http://download.intel.com/embedded/chipsets/specupdate/324212.pdf

[blitz]

Was to be expected at some point. But even on the systems that do support it, it is a pain in the butt to have to rely on legacy emulation.