MOB-2272

* changed maintenance script `wikia/messaging2files.php` to have a tool to upload messages from `messaging.wikia.com` to a file(s),
* imported messages from messaging to `i18n` files,
* added new translations for parent POI categories (translations taken form Jira ticket),
* added logic in model to use translations instead of hardcoded DB data for parent categories.
Not really important, but in general just use `__DIR__` rather than the unnecessary `dirname` function call.