[3064] Culling of Stratholme - second half of the instance implementation

* Allows a complete event run and grant access to all encounters
* Complete cinematics and events
* Achievement and quest support included

ToDo: burning city undead spawn - not yet implemented
      zombies spawn and zombie achievement - not yet implemented

Please make sure that you update to the latest ACID and DB in order to enjoy the full experience!
[3065] Adapt to changeset of 12563

This had been a forgotten commit in my history...

The other uses of GetNearPoint apepar to be fine (huge distance, usually normal mobs)

Also fix a tiny warning in yogg-saron script.
[3066] Spawn scourge waves in the burning part of Stratholme