Fix error checking documented in Issue #45

[cnsnyder]

This PR adds checks for the errors potentially returned in a number of places as documented here : #45

This code is not as DRY as I'd like it, all feedback welcome! I hope to solve issues and improve!

Cheers!

[Lorquas]

Can one of the admins verify this patch?

[subpop]

LGTM

[subpop]

This code is not as DRY as I'd like it, all feedback welcome! I hope to solve issues and improve!

I think there's a follow-up commit or PR we can introduce here that changes the behavior of the showErrorMessages function to return a normal error, instead of a bunch of empty cli.Exit() errors. Then we update the callers of showErrorMessage to check for the returned error and wrap it in a cli.Exit.

[DuckBoss]

LGTM, thanks for the changes.

I had the same thoughts as Link when I saw the showErrorMessages method using cli.Exit(), and I would prefer the logic changes to be in a separate small PR instead of this one.

[subpop]

The commit linter is failing. 650578b contains a capitalized "Fix". It should be lower-case to conform to Conventional Commits. Do you mind amending the commit and changing the message?