Mac OS X building, updating useful script and gitignores!

Hi Sekai devs! I've been doing a bit of unrelated Ponscripter development lately, and figured it'd be nice to contribute to this fork instead of just the one sitting on my local machine not going anywhere.

First thing this PR does is add some more stuff to the gitignore, and make new gitignores for our internal libs. Just some stuff that gets autogenerated and we can safely ignore, not a big change.

I also updated both config.guess and config.sub. Under OS X 10.9, the older versions were seeing my X86_64 processor as an i386, and stuffing compilation a bit.

**Note**
I'm also building this through the command line, rather than through xcode (since I'm more a linux guy at heart). Here's how I build it on my machine (though I have a few things installed with Homebrew):

`CC=clang CXX=clang++ ./configure --unsupported-compiler --with-internal-sdl --with-internal-freetype`

`CC=clang CXX=clang++ make`

Also, sorry about this PR being a little large/expansive. If you want me to chop it down, just let me know.