This removes the need to run c-compilation on one file, and allows us
to in future c++-ify this a bit.
There's a lot of bit-fiddling here that is quite unnecessary, better
error-handling would be nice...
So far this removes a few more unused things (because I would have had
to port them), including:
- Functions with ARITY > 3 (even 3 isn't used, but just so we don't
get complacent)
- Variables
- Most functions moved out of the header, because only te_interp is used.
- The te_print function
