Fix typo in my nickname.
Add Sawteeth player.

It works, but it seems the CPU is slightly too slow for it to work (at
least with the song I chose). And this is without anything else running,
so forget about using this in a game.

I will have to try a different approach.
Merge remote-tracking branch 'pulkomandy/master'
Add a port of LFT's "Hardware Chiptune" player.

* The engine.c/h files are designed to be reusable as a simple sound
engine. This one should be small and light and not waste all your CPU
cycles in fancy filters, mixing and other complex effects.
hwchip: some fixes.

* Wrong mixing of channels (oops)
* Allow to loop the song
* Remove silly "lights" stuff now that it works.
Optimize and cleanup

* Move player to its own file so it is easier to reuse in other projects
* Add some static and inlines to help the compiler optimize stuff
* Replace the music since the original one from LFT doesn't work well
with the modified replay rate. Enjoy the original Boulder Dash music!
(on 3 channels only - 4th is free for sound effects!)
Merge branch 'master' of https://github.com/pulkomandy/bitbox