Highlight edited submissions

[seadowg]

Blocked by #6591

Edits to a submission should be shown in submissions lists (like "Ready to send") as <instance name> (Edit <number of edits since original>).

For example, if I had a submission with the instance name Tree Survey 10/02 and I edited it, I would end up with another submission named Tree Survey 10/02 (Edit 1). If I was then to edit that edited submission, I would end up with a third submission named Tree Survey 10/02 (Edit 2) (and so on).

In the edge case that an editing a submission results in a new instance name, that new instance name should be used with "(Edit x)" postfix. Taking the example above, if the second edited submission changed the instance name to Tree Survey 11/02, then the second edit would be displayed as Tree Survey 11/02 (Edit 2).