Added message at top of page if thesaurus is incomplete

[ulyssear]

What GitHub issue does this PR apply to?

New PR for #636 and #665
Resolves #635

What changed and why?

Adds message at top of page if a thesaurus is incomplete.

(If editing Django app) Please add screenshots

Checklist

• I claimed any associated issue(s) and they are not someone else's
• I have looked at documentation to ensure I made any revisions correctly
• I tested my changes locally to ensure they work
• (If editing Django) I have added or edited any appropriate unit tests for my changes

Any additional comments or things to be aware of while reviewing?

[geekygirlsarah]

This PR is fine, but it's missing the command that was written in #636. Were you going to add that back in?

Never mind, you did #708 for that. I'll merge this in!