Update Smarty to 3.1.21

- add missing block.tphp, block.textformat.php, function.popup.php,
  function.popup_init.php
- update function in function.html_checkboxes.php,
  function.html_options.php

www/Smarty-3.1.21/plugins/modifier.replace.php

@@ -0,0 +1,34 @@
+<?php
+/**
+ * Smarty plugin
+ *
+ * @package    Smarty
+ * @subpackage PluginsModifier
+ */
+
+/**
+ * Smarty replace modifier plugin
+ * Type:     modifier<br>
+ * Name:     replace<br>
+ * Purpose:  simple search/replace
+ *
+ * @link   http://smarty.php.net/manual/en/language.modifier.replace.php replace (Smarty online manual)
+ * @author Monte Ohrt <monte at ohrt dot com>
+ * @author Uwe Tews
+ *
+ * @param string $string  input string
+ * @param string $search  text to search for
+ * @param string $replace replacement text
+ *
+ * @return string
+ */
+function smarty_modifier_replace($string, $search, $replace)
+{
+    if (Smarty::$_MBSTRING) {
+        require_once(SMARTY_PLUGINS_DIR . 'shared.mb_str_replace.php');
+
+        return smarty_mb_str_replace($search, $replace, $string);
+    }
+
+    return str_replace($search, $replace, $string);
+}