Removed warnings from Boost.Random

From: Jens Maurer (Jens.Maurer_at_[hidden])
Date: 2002-02-25 18:04:37

The code in random/detail/signed_unsigned_compare.hpp and
random/detail/const_mod.hpp produced some warnings with
the majority of compilers.  The compilers, from their
limited viewpoint, were correct with those warnings.  I've
now reworked the code so the warnings no longer occor.

I've checked the stuff into the CVS.

Could someone please check out the Windows compilers whether
they can cope?

Thanks,
Jens Maurer