- using the new _READFILE$ and _WRITEFILE commands where applicable
- moved error handler changes inside CopyFile&() so we don't need to remember to do this before calling the function
- fixed file tests complaining about missing error handlers
Current the -o flag will strip any "extension" on the provided filename,
which is fairly problimatic on Linux and Mac OS since those executes do
not have other extensions and names like "foobar.v1" will get the ".v1"
stripped off. This can happen on Windows as well if you leave off the
.exe (QB64-PE will add it for you, but also strip off the existing
extension).
QB64-PE stripping off the ".exe" when provided that on Linux and Mac OS
might actually be useful behavior people are relying on (so that they
don't need to provide different names when compiling on Linux/Mac OS) so
we are preserving that and still removing the extension if it is exactly
"EXE", otherwise we now leave it in place.
Fixes: #297
