compile stylus to css
$ duo --use duo-stylus index.styl > build.css
var co = require('co');
var Duo = require('duo');
var stylus = require('duo-stylus');
co(function *(){
var duo = Duo(__dirname);
duo.entry('index.styl');
duo.use(stylus());
var css = yield duo.run();
// ...
})();
MIT