/**
  * Changes the indents used in EEH_HTML::nl. Often its convenient to change
  * the indentation level without actually creating a new line
  *
  * @param int    $indent can be negative to decrease the indentation level
  * @param string $tag
  */
 public static function indent($indent, $tag = 'none')
 {
     static $default_indentation = FALSE;
     if (!$default_indentation) {
         EEH_HTML::_set_default_indentation();
         $default_indentation = TRUE;
     }
     if (!isset(EEH_HTML::$_indent[$tag])) {
         EEH_HTML::$_indent[$tag] = 0;
     }
     EEH_HTML::$_indent[$tag] += (int) $indent;
     EEH_HTML::$_indent[$tag] = EEH_HTML::$_indent[$tag] >= 0 ? EEH_HTML::$_indent[$tag] : 0;
 }