All Games|Client|SaveGame: Restore object links via a new mechanism
After a save has been loaded, object cross-references haven't always been correctly restored to what they were when the save was made.
The previous method of validating the cross-references was extended to actually restore all cross-references to point to the correct mobjs using the private thinker IDs.
While this obsoletes the cross-reference restoration done by MapStateReaders, the old code still is necessary when loading saves that don't contain the ObjectState info file.
Also noteworthy is that private IDs are persistent across a save and restore.
All Games|Client|SaveGame: Restore object links via a new mechanism
After a save has been loaded, object cross-references haven't always
been correctly restored to what they were when the save was made.
The previous method of validating the cross-references was extended
to actually restore all cross-references to point to the correct
mobjs using the private thinker IDs.
While this obsoletes the cross-reference restoration done by
MapStateReaders, the old code still is necessary when loading saves
that don't contain the ObjectState info file.
Also noteworthy is that private IDs are persistent across a save
and restore.
IssueID #2261