#4 Memory issue debugging patch

[Chad Woolf]

I found making this change to be very useful for debugging memory issues. For debugging purposes it routes everything through genalloc/genfree instead of using the memory table structure. This enables platform tools on OS X to be able to find memory related issues more easily. Scribble, guard malloc, and clang's address sanitizer are a lot more useful.

During a debug build, all you have to do is define MEM_TABLE_SIZE to be zero, and you get the alternate set of macros.

I've included the patch if you find it useful.

[Gary Riley]

Great idea. Changes checked in as r253 and several issues fixed after using scribble and guard malloc checked in as r254.