Add notification about remote filter releases?

[SirLich]

We could store the git SHA of the installed commit, and then do a quick check to see if anything needs to be updated?

Not sure if better to auto-run when compiling, or add a check command?

The default rn is that filters will easily get out-dated, since even running regolith install will skip satisfied dependencies. You have to manually delete (or did we add command to clear out the tmp directory?) before reinstalling.

[SirLich]

See #74

[MedicalJewel105]

I would add a command
update_filters or so