docs: function clean (args, cb) {
    if (!cb) cb = args, args = []
    if (!args) args = []
    args = args.join("/").split("@").join("/")
    if (args.substr(-1) === "/") args = args.substr(0, args.length - 1)
    rm(path.join(npm.cache, path.normalize(args)), cb)
  }