[X] Menu for direct messages
	[X] Commands for new user registration
	[X] If registered/online -- responding to PMs (always require prefix)

[X] Open upstream connections
	[X] when registered users join the groupchat
	[X] open existing connections at app startup

[ ] Handle upstream messages
	[X] System messages
	[X] Public messages
		[ ] Coalesce matches from multiple upstream connections (timer?)
		[X] Exclude messages from hub-security (custom nick)
		[ ] Allow sending public messages to DC from inside the group chat
		[ ] Nick translation
	[X] Private messages
		[X] Send directly to telegram user account (even if they're telegramuser-on-dc - telegramuser-on-dc PMs i guess)
		[X] Allow replying to PMs with /pm [recipient] message

[X] Graceful termination
	[X] Ability to close nmdc connections
	[X] Close nmdc connection && deregister user (with bot message) when user leaves groupchat

[X] Block unknown users from entering telegram channel

[ ] Attachment support
	[ ] Convert telegram files/images/videos to raw URLs for NMDC
		[ ] Bot API does allow downloading - but (?authenticated)? need to re-host (either internally or upload to contented server)
	[ ] Contented support - convert known URLs with image mime type to telegram images
	[ ] Including private messages??? is that possible?

[ ] Publish