DynamicSettings should support the total configuration of user groups; this includes managing the default user groups associated with a wiki. At the moment, it can only add new groups, but cannot modify existing groups.

One solution to this is to set $wgGroupPermissions = []; in the global LocalSettings.php file, which will remove all of the default groups (but not those added by extensions). We can then load default groups in via the database.

Also, the current set up is that permissions to deny is added to the 'deny' box, but we can do away with this since we will be only adding the relevant user rights per group, we don't need to deny any since we will assume that if a permission is not explicitly granted, then it is denied.