Data Model

Conversation	Message	Device	User
messages: List<Message>	sender: Device	userid: String	userid: String
clanks: Map<Device, DoubleClank>	conversation: ConversationID	deviceid: u32	devices: List<Device>
id: ConversationID	id: MessageId	signing_key: PublicKey
my_clank: TripleClank	text: String	active_since: Activation
	OP: Option<MessageId>	deprecated_since: Option<Deprecation>
	attachment: Blob
	sent: UTC
	doom: UTC

TripleClank	DoubleClank	Activation	Deprecation
ratchet: KdfKey	ratchet: KdfKey	timestamp: utc	timestamp: utc
pubkey: KxPubKey	pubkey: KxPubKey	signed_with: DeviceId	signed_with: DeviceId
seckey: KxSecKey		signature: Blob	signature: Blob
		new_key: PubKey