code: public static String open(Tag tag, AttributeValue... attrs) {
  
          StringBuffer sb = new StringBuffer();
          sb.append("<").append(tag.name());
          for (AttributeValue attr : attrs) {
              sb.append(" ").append(attr.toString());
          }
          sb.append(">");
          return sb.toString();
      }
docs: Generates an opening tag.<p>
  
  @param tag the tag to use
  @param attrs the optional tag attributes
  
  @return HTML code