code: function serveReadme (req, res, next) {
    res.set('content-type', 'text/html')
    Promise.all([
      require.resolve('github-markdown-css'),
      path.join(__dirname, '..', '..', 'README.md')
    ].map(function (item) {
      return fs.readFileAsync(item, 'utf8')
    }))
      .then(function (contents) {
        res.send(
          '<!doctype html>' +
          '<html>' +
          '<head>' +
          '<meta charset="utf-8">' +
          '<title>Shutter - README.md</title>' +
          '<style type="text/css">' +
          contents[0] +
          '</style>' +
          '</head>' +
          '<body>' +
          '<div class="markdown-body">' +
          marked(contents[1]) +
          '</div>' +
          '</body>' +
          '</html>'
        )
        res.end()
      })
      .catch((reason) => {
        log.error("Can't serve README.md", reason)
        res.status(200).send()
      })
  }
docs: TODO Cache this page