Merge the GO changes dfighter2->Master part 3

Removed method GameObject::IsQuestGiver.
Added new methods GameObject::IsActive, GameObject::GetFlags, GameObject::SetFlags
Some cleanup and refactoring, will now use GetFlag, SetFlag, IsActive, Deactivate, Activate instead of setting/getting these values with Set/GetUInt32Value methods.

TODO: GameObject.h, remove enum Gameobject_bytes needed by:
Quest_BladeEdge_Mountains.cpp, IsleOfConquest.cpp, RingOfValdo.cpp