Bring the textbox blocktype's render_instance method signature into alignment...

Bring the textbox blocktype's render_instance method signature into alignment with what it should be.

htdocs/blocktype/textbox/lib.php

@@ -44,7 +44,7 @@ class PluginBlocktypeTextbox extends SystemBlocktype {
         return array('portfolio', 'profile');
     }
 
-    public static function render_instance(BlockInstance $instance) {
+    public static function render_instance(BlockInstance $instance, $editing=false) {
         $configdata = $instance->get('configdata');
         $text = (isset($configdata['text'])) ? $configdata['text'] : '';
         safe_require('artefact', 'file');