code: function lintConfig(config) {
    if (!config.path) return logger.halt('null config.path')
    if (!config.path.root) return logger.halt('null config.path.root')
    if (!config.path.client) return logger.halt('null config.path.client')
    if (!config.path.static) return logger.halt('null config.path.static')
    if (!config.path.vendor) return logger.halt('null config.path.vendor')
    config.path.client = config.path.client.replace(/\/$/, '')
    var staticDir = path.join(config.path.root, config.path.static)
    config.$path = {
      source: {
        client: path.join(config.path.root, config.path.client),
        vendor: path.join(config.path.root, config.path.vendor)
      },
      target: {
        static: staticDir,
        client: path.join(staticDir, config.path.client),
        vendor: path.join(staticDir, config.path.vendor)
      }
    }
    return config
  }
docs: guard config
  
  @param  {Object} config
  @return {Object}