win32 extras and embedding

win32 extras and embedding

This patch makes the various Win32-specific builtins available
in embedded perl.

It also fixes a problem with FP errors thrown by the Borland
runtime when doing something like C<perl -e "print(1.0e+26 % 1">.
The VC runtime doesn't throw those errors because FP errors are
off by default in VC, on in Borland.  The patch adds code to always
turn them off.  (This should ultimately be made user-settable via
$SIG{FPE}, when we have more robust signal handling).

I've also made Borland builds use gcvt(), which is available there,
and is much faster than sprintf().

Most of the size of the patch comes from moved code.

[editor's note: some of these changes are being applied in the wrong
order and changing slightly]

p5p-msgid: 199707250232.WAA03421@aatma.engin.umich.edu