Precompile build scripts.

This saves time running them through the CoffeeScript compiler every
time we build a file.
Revamp stylus-dep.

The new stylus-dep hijacks the stylus compiler, reporting all the styl
files it opens. This allows the CSS and dependency file to be compiled
at the same time and in the same process, saving some time.
Merge pull request #2 from benbria/optimization

Optimization