Finish keyboard driver

With the interpretation/distribution of keycode actions, the keyboard driver
is done (for now - maybe programs want to read keystrokes later, i.e.
something that is associated with the stub 'stuff_queue' function).

I created lots of files to export most of the various interfaces defined by
the precious concepts. Now they must be breathed life into :-) Essentially
everything that has to do with logic is still missing, like building the
thread stack or the thread structure per se. I'm going to miss C somwhat
more from now one but I think it's worth the trouble as I want to port my
Sieve of Eratosthenes to notos later on - completely in assembly.

Rename kern.{tmp,img,lds} to notos.{tmp,img,lds} to avoid name collision
with the kernel/ directory in the first four characters. It's annoying to
not be able to use Tab to get in there.