[oi-dev] Rust lang for oi

[Carsten Grzemba]

I could successfull build and package rust for OI

https://github.com/cgrzemba/oi-userland/tree/rust/components/developer/rust

The build of rustc requieres an already working rust compiler.

On my first attempt I pulled the compiler from joyent.

But for subsequent builds we can use our own pre version rustc for 
stage0 bootstrap compiler.

I would do some tests and create than an PR.