Sort achievement categories

app/Models/AchievementCategory.php

@@ -16,6 +16,16 @@ use Illuminate\Database\Eloquent\Relations\HasMany;
  */
 class AchievementCategory extends Model
 {
+    const array ORDER = [
+        'number_of_flights',
+        'distance',
+        'general_flying',
+        'countries_and_continents',
+        'aircraft',
+        'airlines_and_alliances',
+        'fun_challenges',
+    ];
+
     protected $fillable = [
         'internal_name',
         'name',