* Add preliminary support for TTY Serial/UART (#15)
* Use shadow_buffer instead of VGA buffer to get a framebuffer-agnostic TTY supprot
* Added menu browsing & inputs from Serial TTY (#15)
* Add fix for degree symbol on TTY. Correct serial.c & serial.h file created with CRLF (#15)
* Move tty_error_redraw() to insure correct redraw when a error occurs
* Many reindent / cleanup
* Various optimization from @martinwhitaker comments