Message highlights for moderators

[Monadic-Cat]

Much like a certain other bot we currently use, it'd be nice if we could set words to notify ourselves when they're said, except without the limit of 20.

[GnomedDev]

There are bots exclusively for this, including Highlight (292212176494657536). Seems like duplication of effort to implement this in Ferris.

[ivandardi]

The question is if we'd like to add another bot to the server just to handle that. Considering the current vulnerability issue with Carlbot, I think we need to think a bit before we do anything. I'll check with the rest of the moderation team.

[GnomedDev]

Highlight only needs limited permissions, basically just read messages to my knowledge, so there isn't going to be an issue with it going rogue (it is also owned by the maintainer of discord.py).