add mechanism that visually marks abstraction objects that are edited but unsaved (dirty)

add mechanism that visually marks abstraction objects that are edited but unsaved, and all their ancestors. This feature allows the user to easily identify the location of unsaved but edited abstractions that could cause problems and unwanted behaviour.

Was originally included in the WIP patch 'patch private abstractions [ab]'. It has been separated because it doesn't belongs to it, conceptually.

Preview:

The colors can be changed if red and orange are not adequate.

Looks good, I'll go ahead and merge.

As we discussed, I think the bigger problem with abstractions is a user having multiple dirty instances and accidentally overwriting one of them. So we need either:

1. Warning dialog when the 2nd instance is dirtied, or
2. Confirmation dialog on save to ask if they are sure they want to overwrite the other dirty abstraction(s).

I personally like number 1, but I can imagine it frustrated a lot of users. So maybe 2 is the best-- users already expect a dialog on save, so no surprises there.

merged

Great!

resolved all threads