[gforth] buffer overflow in swig extension

[Reepca Russelstein]

In Lib/forth/header.swg, in the forth-capable swig, in
swigFloatConstant, a buffer of size 128 is used to hold the result of
an sprintf. Unfortunately, in attempting to generate an interface to
GLU (not my choice of what to use, before anyone asks),
GLU_TESS_MAX_COORD is 1.0e150. So some
I-assume-important-because-lacking-it-causes-a-segfault stack
information gets overwritten. Perhaps we could change that buffer size
to a higher number, or get it to use scientific notation for huge
numbers?

On a somewhat unrelated note, I remember reading about a forthnet
project where fsi files (among other things) could be found, but
didn't manage to find a link to that. Any info on that?

Thanks.