add upload permission flags

GSALLOWUPLOADS - toggle uploading
GSALLOWUPLOADCREATE - toggle folder creation
GSALLOWUPLOADDELETE - toggle file/folder deletion
uses upload.php as filebrowser

No longer have to maintain 2 sets of code for cke filebrowser support

just add ?browse to upload.php
all cke binding is done in js, migh thave to adjust stuff for other uses
of filebrowser

add generic func callback support for plugins selectors, and add back in
cke func and langcode