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.spacify.php

@@ -0,0 +1,27 @@
+<?php
+/**
+ * Smarty plugin
+ *
+ * @package    Smarty
+ * @subpackage PluginsModifier
+ */
+
+/**
+ * Smarty spacify modifier plugin
+ * Type:     modifier<br>
+ * Name:     spacify<br>
+ * Purpose:  add spaces between characters in a string
+ *
+ * @link   http://smarty.php.net/manual/en/language.modifier.spacify.php spacify (Smarty online manual)
+ * @author Monte Ohrt <monte at ohrt dot com>
+ *
+ * @param string $string       input string
+ * @param string $spacify_char string to insert between characters.
+ *
+ * @return string
+ */
+function smarty_modifier_spacify($string, $spacify_char = ' ')
+{
+    // well… what about charsets besides latin and UTF-8?
+    return implode($spacify_char, preg_split('//' . Smarty::$_UTF8_MODIFIER, $string, - 1, PREG_SPLIT_NO_EMPTY));
+}