Save change-histories for records

[JoselleAstrid]

So anyone can see what was changed, when, and by who (the player or a moderator/verifier). This includes filters, proof links, verification status, date, comments, etc.

The record value itself (the time or speed) normally wouldn't be editable by the player, since improvements should be submitted as new records rather than as edits. However, in the event of a typo, the player could notify a mod that it needs correcting.

Each edit should also have a comment field available, where the editor (the player or a moderator) can explain why the record was edited that way. This probably wouldn't apply to verification, though (which would just involve ticking a box).