Indicate when other users are typing

[spoulson]

It is generally not possible to know when any given user is typing on the IRC network, except if they're also using Chatmore.

For all Chatmore users, send a signal when a user is actively typing a message. This signal can be relayed to other users on the same network and channel.

The typing signal should not occur when the message starts with a slash, indicating the user is typing a client command, not a channel message.

Unknowns: How to share this signal with Chatmore users in the same channel and network. How can it be known when users are on the same network when IRC server nodes may vary? Send special encoded private messages that only Chatmore can parse?