Removed strategies for Naxxramas until they can be rewritten without core changes (#1961)

Merging this isn't required but rather to provide an option to core
changes.

The scripts can be written from scratch when someone feels like doing it
without touching the core.

This shouldn't be merged unless
https://github.com/mod-playerbots/azerothcore-wotlk/pull/130 is merged
too.

src/PlayerbotAI.cpp

@@ -1503,9 +1503,6 @@ void PlayerbotAI::ApplyInstanceStrategies(uint32 mapId, bool tellMaster)
         case 532:
             strategyName = "karazhan";  // Karazhan
             break;
-        case 533:
-            strategyName = "naxx";  // Naxxramas
-            break;
         case 544:
             strategyName = "magtheridon";  // Magtheridon's Lair
             break;