Not actually being used yet since it needs a chunk of work to integrate cleanly with how I assume prefabs work. The algorithm is theoretically there though.

This was way more annoying to figure out because the API docs for PrefabUtility.GetPropertyModifications() tell you literally nothing of value

- Handles prefabs being linked that don't have U# behaviours now
- Added exception handling that falls back to unsorted prefab set and logs an error in the case of a failure
- Turned assertions into exceptions because assertions don't give enough info

Random thing I saw and wanted to make more consistent

- Fixed marking deltas on prefabs for pre-pass because Unity's API for this is not documented at all and the API itself is the most confusing to use API you could imagine.