Add options to zig compile

[dantecatalfamo]

Support for compiling with raygui, raymath, and physac.
Also outputs the required headers.

addRaylib gains an additional positional argument that takes an Options struct.

Raygui should be located ../raygui relative to the repo root
Physac should be located ../physac relative to the repo root

These locations match the options in the Makefile

One step generates src/raygui.c, src/raymath.c, or src/physac.c with the [lib]_IMPLEMENTATION macro defined depending on which are enabled

[raysan5]

@dantecatalfamo physac shouldn't be included, the library is mostly abbandoned and has issues.

EDIT: Also note that raymath is already compiled into raylib, adding it could generate issues.

[dantecatalfamo]

Okay, I've removed physac.

EDIT: Also note that raymath is already compiled into raylib, adding it could generate issues.

Oh I didn't see it was pulled in by rcore, I've removed the generated file 🙂

I set it to always install rlgl.h and raymath.h because the Makefile also does that.

[raysan5]

@dantecatalfamo Thanks for the improvement!