Merge pull request #10 from swiftcoder/0.1-alpha.0

Extended Marching Cubes and Dual Contouring

Add marching cubes using linear hashed octrees.

Accompanying improvements:
- Refactors common code out of the base marching cubes implementation.
- Adds a 3 dimensional vector class to improve readability.
- Apply rustfmt to entire codebase.
- Main sample now can switch algorithms, shapes, and wireframe mode on the fly.
- Samples can now all be exited by pressing the ESC key.

Add normal extraction support to marching cubes

Also hoist CentralDifference into the public API.

Point cloud extraction and deferred rasterisation example

Also Factor some common code out of individual examples.

Release 0.0.1