Palantir fixes

1) Both NerbyQuests and QuestsDetails API moved to Palantir controller
2) Changed response schema: 'location_x' -> 'latitude' abd 'location_y' -> 'longitude'
3) NearbyPOISearchService: perform search only inside current wikia
I think [`is_numeric`](http://us2.php.net/manual/en/function.is-numeric.php) should suffice here as well.