MDL-48371 editors: Option for removing managefiles

We want to remove the managefiles button from the
editors in the wiki so that students don't delete
each others files.

lib/form/editor.php

@@ -53,7 +53,7 @@ class MoodleQuickForm_editor extends HTML_QuickForm_element {
     /** @var array options provided to initalize filepicker */
     protected $_options = array('subdirs' => 0, 'maxbytes' => 0, 'maxfiles' => 0, 'changeformat' => 0,
             'areamaxbytes' => FILE_AREA_MAX_BYTES_UNLIMITED, 'context' => null, 'noclean' => 0, 'trusttext' => 0,
-            'return_types' => 7);
+            'return_types' => 7, 'enable_filemanagement' => true);
     // $_options['return_types'] = FILE_INTERNAL | FILE_EXTERNAL | FILE_REFERENCE
 
     /** @var array values for editor */