[ANN] simple_units: physical units for Rust

Hi Rustaceans,

this crate provides a simple physical unit system for Rust:


It is very simple and unfortunately doesn't scale since every unit (and combination of units) needs to be defined.
There are a bunch of macros to make it easier but it's still very hacky.

But for simple units it works quite nicely:

    let length = Meter(20.72);
    let time = Second(12.39);
    // Resulting type: MeterPerSecond
    let velocity = length / time;

    // This will not compile:
    // let error = length + time;