travis integration
Add mechanism to write private messages
update README
Remove prn, fix indentation
Use smack fork while we wait for canonical

canonical 3.4.1 version is not yet released, so let's use a
forked one to simplify deployment (on travis, for instance)
Merge pull request #3 from paraseba/forked-smark-clojars

Use smack fork while we wait for canonical
Add travis status img to readme
Ack standup update received
Ack what updates were received
Don't ack a message without an update

Users will get used to only receive positive ack messages. There's no
need to ack for messages without updates
Update ack message to work with new private-message fn
Handle updates received via private messages