docs: function readFile(options, href) {
  	var filePath = path.join(path.isAbsolute(href) ? options.root : path.dirname(options.from), href);
  
  	return new Promise(function (resolve, reject) {
  		return fs.readFile(filePath, 'utf8', function (err, res) {
  			return err ? reject(err) : resolve(res);
  		});
  	});
  }