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Added
- Forward `JOIN`, `PART`, `NICK`, and `QUIT` messages from IRC.
- Forward member joining and leaving messages from Matrix.
- Send membership change messages as notices to Matrix rooms.
Changed
- One client/connection per IRC network or Matrix server.
- Channels in the same network/server are joined by the same client.
- Include Matrix user's display name in forwarded messages.
- Reconnect to network/server on encountering error.
- Use angle brackets (i.e., `<` and `>`) to delimit sender name in
forwarded messages.