Shorthand "Paste to ..." message

[Vogel612]

It's a pain to always write "Don't paste code, use [favorite pasting provider] instead"

How about a simple series of things we can tell people as an expansion to the tell command.
The series could be configurable using a properties file.

Also it would be nice to be able to add and edit messages for that. I imagine the following:

!!tell user pasting

!!canned-messages edit pasting "Don't paste code ..."
!!canned-messages add asking "Don't ask to ask ..."
!!canned-messages remove asking

[Unihedro]

in this specific case we can always just move the message to the Do not dump code, use Pastie.org, GitHub gists or Pastebin.com room, but this is a good feature.

[Vogel612]

This can (and possibly should) be used instead of automation for #53