code: function applyShortcut(content, shortcut) {
      var start = shortcut.getStart();
      var end = shortcut.getEnd();
  
      var tagStart = shortcut.getStartTag();
      var tagEnd = shortcut.getEndTag();
  
      var regex = new RegExp(
          escapeStringRegexp(start) + '([\\s\\S]*?[^\\$])' + escapeStringRegexp(end),
         'g'
      );
      return content.replace(regex, function(all, match) {
          return '{% ' + tagStart + ' %}' + match + '{% ' + tagEnd + ' %}';
      });
  }
docs: Apply a shortcut of block to a template
  @param {String} content
  @param {Shortcut} shortcut
  @return {String}