Configure for Apple and guard malloc include

[myshen]

[justinmuller]

I had been doing this manually each time I updated, good work @myshen. But, what is the commit of sha3.cpp for? How is this related to building on Darwin?

[myshen]

Good question, I screwed up. I've removed the sha3.cpp. I hope I didn't do it the wrong way.

[coercion]

OS X doesn't need a malloc include. This is what I've been patching with.

#ifndef __APPLE__
#include <malloc.h>
#endif

[myshen]

Updated to use @coercion's method.