Refactor ; and k to use new NEXT-INSTRUCTION function
Change k semicolon behaviour
Documentation fixes
Refactor CHAR-AT
CHAR-AT now expects two ints, and CHAR-AT-VECTOR is equivalent to the
old CHAR-AT function
Refactor Funge-space into a struct
We'll need to store more information in each F-SPACE object, so start
off by refactoring it into a struct
Negative funge-space
The three negative quadrants of funge-space are accessed WAY less often
than the positive quadrant in the majority of cases, so we use a simple
HASH-TABLE for negative co-ordinates.
Division by zero results in 0 in funge-98