[Python-Dev] Get rid of strerror.c and memmove.c?

[Brett Cannon]

I ran LLVM's under-development C front-end, clang
(http://clang.llvm.org), against Python today. While a ton of message
crop up thanks to lacking header files, I did come across a handful of
semi-useful warnings (e.g., the change I checked into
Python/compile.c).

One thing it picked up is that on OS X Python/strerror.c disagrees
with the declaration of sys_nerr and such. But then I thought I
remembered strerror() being in C89. I checked configure-in to make
sure that it wasn't special for some reason, it it isn't; only used
when the function is not normally available. Same goes for memmove().

Since both strerror() and memmove() are both in C89 (they are listed
in K&R), can we ditch these files?

-Brett