KAZOO-812: Unable save $0 transactions
KAZOO-813: Fix update callee id when missing account id
KAZOO-818: Fix created/ended time on transactions apis
resolve KAZOO-826: handle_event is already spawned now so we can not use self()
Fix: View transactions as we now support $0 amount transactions it was craching one of the view as 0 in js in falsy value !! Dat javascript!
KAZOO-543: formatting and remove logging
KAZOO-543: add clauses to rid ourselves of unnecessary logging
KAZOO-543: log current agents known by queue
KAZOO-543: add specs
KAZOO-543: match unused casts in gen_listeners
KAZOO-543: play error if device has multiple owners
KAZOO-543: start agent only in queue

if an agent is logged out, and uses the queue_login callflow, only log the agent
into that queue (even if they're configured for others).
KAZOO-543: if agent has no endpoints, log them out
KAZOO-543: add start_link with explicit list of queues to log into
KAZOO-543: update agent status on queue_login if not logged in in general
KAZOO-543: persist queue login/logout information

If an agent logs in or out of a queue via the queue_* callflows,
persist that change into their stored config.
KAZOO-543: allow agent pause of 0 to be unlimited pause
KAZOO-543: handle unhandled message from gen_listener
KAZOO-543: don't change state on outbound call when paused
Merge branch 'v2.13'