Update 0.32

Point clouds are still in progress, only used for stones now, but I did some bugfixing so here's a work-in-progress update.

• Fixed (hopefully) the "can't create saved game file" bug.

• Point cloud models for various stones.

• Added point cloud quality setting.

• Menhir circles use single type of stone object for the circle now.

• Changed how static objects are created for better mod-ability.

• Optimized some parts of world generation.

• Switched random number generator to faster and better xorshift* algorithm.

• Lighting/shading is somewhat off temporarily while transitioning to point cloud models.