This has smashed the keydest handling for many things, and bindings, but
seems to be a good start with the new input system: the console in
qw-client-x11 is usable (keyboard-only).
The button and axis values have been removed from the knum_t enum as
mouse events are separate from key events, and other button and axis
inputs will be handled separately.
keys.c has been disabled in the build as it is obsolute (thus much of
the breakage).
Input Mapping Tables are still at the core as they are a good concept,
however they include both axis and button mappings, and the size is not
hard-coded, but dependent on the known devices. Not much actually works
yet (nq segfaults when a key is pressed).
This refactors (as such) keys.c so that it no longer depends on console
or gib, and pulls keys out of video targets. The eventual plan is to
move all high-level general input handling into libQFinput, and probably
low-level (eg, /dev/input handling for joysticks etc on Linux).
Fixes#8
