mcopt 0.3.0-alpha.2

Second alpha of mcopt without Sodium.

• Distant Horizons now works with mcopt's own renderer: its LODs draw on Metal. Set Distant Horizons to its OpenGL renderer and mcopt switches to OpenGL for it.
• Mods that require Sodium, such as Iris or Better Block Entities, can't be used with this build.

Thanks to @CazzaCoder for Distant Horizons on the Metal renderer.

Still alpha: expect bugs, and back up your worlds.