Utilities to allow getting and setting our AssetImportData to an asset from a base UObject*. Note that not all asset types support AssetImportData, and in some cases when retrieving it for e.g. a Skeleton, we'll actually check it's preview mesh instead (since Skeletons don't have AssetImportData). The setter won't do anything if you try setting asset import data on e.g. a Skeleton, on the other hand.