Optimization

Two changes:

- Precompiled build scripts: the scripts in the `/scripts` folder are precompiled (using `cake scripts`), which saves a little time.
- `stylus-dep` is rewritten, removing the ad-hoc logic and simply hooking into the stylus compiler, meaning only one pass over the stylus files is needed to both compile and find dependencies.

This brings the Loop `ninja debug` time from 55s to 45s for me.