BASIC compiler

[Will Coleda]

The BASIC compiler is now (kind of?) working again after the 0.3.0  
release. Updates to the new calling conventions. No longer trying to  
manage the conventions in near-PASM level code.

The windows display code is just commented out, but several of the  
samples in the compiler (inc. conn4, hanoi) now seem to work.

If you find any problems, please open a ticket.

Regards.