Auto-close deleted polls

[dhouck]

There should be an option on servers so that when the message which contains a poll is deleted, that poll is closed. It's natural for admins to delete messages they do not want, and pm!close is bot-specific.

This way, they won't clog up the label namespace, and they won't show up to pm!show

[matnad]

You can delete polls with pm!delete to clear up the namespace. I will look into this as an alternate option to closing polls but I have to first see how it would interact if the same poll is active in multiple channels.