Removed duplicate usb code, move to usb_serial_hid.c/h
fix typos, remove test code + slight refactoring
remove stdio.h to save space
Commented most of usb_serial_hid.c
tidied up usb_serial_hid.c
some design pictures
Merge pull request #7 from JamesGlanville/master

Cleaned up and commented most of the usb code
Add automatic build dependency generation

Add automatic generation of build dependencies for build targets. Slim down the
includes to only pull in what is actually used in the different C-files.