Use Gulp instead of Grunt

Like this?
``` coffee
root = './main'
static = "#{root}/static"
paths =
paths.clean = [
  "#{static}/dst"
  "#{static}/ext",
  "#{static}/min"
]
paths.watch = [
  "#{static}/**/*.css"
  "#{static}/**/*.js"
  "#{root}/**/*.html"
  "#{root}/**/*.py"
]
```