- add additional migration files

- add seeder for collections
- coverage x_min, x_max, y_min, y_max
- SitelinkController db-independent

database/seeds/DatabaseSeeder.php

@@ -29,6 +29,7 @@ class DatabaseSeeder extends Seeder
         $this->call('LicencesTableSeeder');
         $this->call('LanguagesTableSeeder');
         $this->call('PagesTableSeeder');
+        $this->call('CollectionsTableSeeder');
         $this->command->info('User table seeded!');
     }
 }