Crust compiler

[mbwilding]

So I made modifications to the rust toolchain.

1. Unsafe checks removed
2. Variables are mutable by default (let rather than let mut)
3. Mutable pointers by default (Can use pointers like * instead of *mut or ** rather than *mut *mut)

Just a proof of concept of what Crust could be with a bit of effort.
Would be cool to see azozin implement the pub by default stuff.

Raised this PR mainly to spark something in people. Don't expect it to get merged as it would require a custom pipeline to apply patches to rust and publish releases.

The Crust version of the Rust toolchain is here: https://github.com/mbwilding/rust