Removes a role from WordPress.
NB: This setting is saved to the database (in table wp_options, field wp_user_roles), so it might be better to run this on theme/plugin activation
<?php remove_role( $role ); ?>
<?php remove_role( 'subscriber' ); ?>
When a role is removed, the users who have this role lose all rights on the site.
remove_role() is located in