User country mapping; ignore unused groups #443 (#584)

* Fix the user country import #443

* Ignore the old "core" groups because they're unused #443

* Properly sync roles and individual permissions #443

app/Services/RoleService.php

@@ -39,7 +39,7 @@ class RoleService extends Service
     {
         // Update the permissions, filter out null/invalid values
         $perms = collect($permissions)->filter(static function ($v, $k) {
-            return $v;
+            return !empty($v);
         });
 
         $role->permissions()->sync($perms);