- Lots of indenting changes
- VC++ is strict with variadic macros
- VC++ does not accept unistd.h
- new interface for walltime
- VC++ does not seem to have support for integer overflow.
- VC++ defines YENV_REG?
- no access flags, x permissions ignored.
- new FindGMP supporting MPIR
- make horus optional (c++ is hard).
get rid of string I/O, did not add much
getc is never actually used by Prolog
try to use system I/O, even if it may be slower, at least for now.
extend IO C-interface to allow reading clauses
