Ongoing GMP developments

[Torbjorn Granlund]

I have removed the K&R support from the head.  (It will remain in 4.3
and 5.0, of course.)  This simplified the Makefiles a bit.  We're
working on generalisations of the GMP build system, to allow for some
arcane build system, so simplifications are nice.

How about removing the mpbsd functions?  They were useful when GMP was
new, but nowadays I really doubt anybody uses them.  Would *you* miss
these functions?

Now it is possible to compile head with a C++ compiler (thanks to Marc
Glisse for some help with C++ advice!).  This is in preparation for
further abtracting the mp_limb_t when C++ is used, when compiling GMP is
a special mode...

-- 
Torbjörn