Twitchirc

- minor: Reformat moderation.py
- minor: Add a missing pair of parenthesis

- Fix bug to do with duplicate messages.

- Make avoiding duplicate messages work. Currently cannot disable this functionality or change the character.

- smol bugfix

- fix spam reconnect bug

- addition: whisper commands
- minor fix: Make all `Message`s be imported into `__init__`
- minor addition: new `available_in_whispers` parameter for the `Command` constructor and for `Bot.add_command()`
- minor addition: `WhisperMessage`s will now "quack" like `ChannelMessage`s, added `channel`, `user` properties