Add support for tag namespaces

Namespaces are of the form tag:namespace and can be infinitely nested
ala tag:namespace:supernamespace etc

classes/misc.class.php

    */
   public static function sanitize_tag($Str) {
     $Str = strtolower($Str);
-    $Str = preg_replace('/[^a-z0-9.]/', '', $Str);
+    $Str = preg_replace('/[^a-z0-9:.]/', '', $Str);
     $Str = preg_replace('/(^[.,]*)|([.,]*$)/', '', $Str);
     $Str = htmlspecialchars($Str);
     $Str = db_string(trim($Str));

classes/torrentsearch.class.php

           $Operator = self::$FieldOperators[''];
         }
         if (!empty($QueryParts['include'])) {
+          if ($Field == 'taglist') {
+            foreach ($QueryParts['include'] as $key => $Tag) {
+              $QueryParts['include'][$key] = '( '.$Tag.' | '.$Tag.':* )';
+            }
+          }
           $SearchString .= '( ' . implode($Operator, $QueryParts['include']) . ' ) ';
         }
         if (!empty($QueryParts['exclude'])) {