[MISC] The Version Checker

[smehringer]

SeqAn behaviour (current):

app user = e.g. someone using raptor
app developerr = e.g. Enrico

Call server with current seqan version and current app version. And then:

1. Notify user if there is a newer app version
2. Notify app developer if there is a newer SeqAn version than the current
3. Notify app developer if current app version is newer than the one registered online

I think 1. and 3. can stay as is.

**But what to do about 2. **

a. Do we notify about the sharg version instead? (I guess)
b. But: What happens when we include sharg back in seqan3. Do we still report the sharg version? Since seqan3 would need to update sharg not the app developer using seqan3. Then it's more interesting to update seqan3?

For now we could implement a) and worry about b) when we backport sharg to seqan3.

• Alter version checker when only using sharg, to call the sharg version
  • Done by [FEATURE] Adapt the version checker to sharg. #38
    Open Todo:
  • [DOC] Move Update notification information into sharg documentation #83
• When we backport sharg to seqan3 we need to
  • call sharg and seqan3 version
  • user should ONLY be notified about a seqan3 version now, NOT sharg
  • Our CI should check if seqan3 includes the newest sharg
  • The unusal use case, that sharg AND seqan3 are included will be solved by customising the submodules dir