#UE4 Deprecated ULevelStreaming::PackageName in favor of the new WorldAsset TAssetPtr. This will allow editor tools to properly follow references from persistent levels to sublevels. All existing usage of PackageName has been replaced with GetWorldAssetPackageName() and SetWorldAssetByPackageName().
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Integrated using branch Ue4-To-UE4-Fortnite-Simple (reversed) of change#2269772 by Bob.Tellez on 2014/08/24 16:49:38.
[CL 2269774 by Bob Tellez in Main branch]
Refactored some of the UI code for ULevelStreaming to use PostEditChangeProperty so it's more reuseable.
#codereview matt.kuhlenschmidt,dmitriy.dyomin
[CL 2222165 by Chris Gagnon in Main branch]
- Added icons to level hierarchy to distinguish level streaming methods
- Added tile coordinates offset when umporting tiled heightmap
[CL 2047641 by Dmitriy Dyomin in Main branch]
