note-type-specific commbadge emails (bug 1043541)

- Create a mapping from ```note_type``` -> email template name.
- Change email titles to be relevant to the note type (e.g., ```Rejected: Facebook```).
Upon further inspection I see that zamboni does not have a URL for this. Could we add one after `'/comm/.*'` so that it can't be hit but we can still treat it like a valid URL?