code: function getExcerptByMoreTag(file, regExp) {
      var excerpt = false,
          contents = file.contents.toString();
      contents = cheerio.load('<root>' + contents + '</root>', {decodeEntities: false})('root').html();
      var match = contents.search(regExp);
      if (match > -1) {
          excerpt = contents.slice(0, match);
          excerpt = v.unescapeHtml(excerpt);
      }
      return excerpt;
  }
docs: retrieve excerpt from file object by extracting contents until a 'more' tag
  
  @param  {Object} file   file object
  @param  {RegExp} regExp 'more' tag regexp
  @return {mixed}         excerpt string or false