Clear indication that mod in compress merged mod set has updated

[MattMills]

Is your feature request related to a problem? Please describe.
It's unclear when a mod in a compress merged mod set has been updated and needs to be re-merged.

Describe the solution you'd like
IMO an updates available icon would be ideal, and shouldn't be incredibly hard to implement although I don't know if mods are versioned anywhere in an identifiable way. Feel free to close if not desired, I just think it'd be nice.

Describe alternatives you've considered
N/A?

Additional context
Nope.

[bcssov]

Note for future reference: Irony does not track merged mods one to one in any way shape or form; it was never designed to do so. If this ever is being considered the whole infrastructure of mod merge tracking needs to be done first, After that one can consider implementing this feature.