Add cui
Put ui stuff in separate file
Add xmpp client
Glue ui and xmpp code
Remove /identity command

We use other mechanisms now
Don't use ourJid anymore
Glue with axolotl ratchet

We now save the private key on startup and create a new ratchet
for each contact, each time with the same private key.
Fix ratcheting + implement receive message

Now each contact gets its own ratchet that is initialized when we
query for axolotl parameters.