Adds promise.calls
Remove duplicated tests cases
Allow 'None' type in tables and arrays
Revamp heartbeat handling

Be conservative in heartbeat behavior: send at the minimum interval
negotiated by the server and the client, and do not artificially abort a
connection if we do not receive any heartbeats.
use a monotonic clock instead

This transplants the monotonic backport from kombu into this package,
and uses it for heartbeats.
refactor heartbeats to follow rabbitmq-java-client's model
Merge branch 'dfa/master'
Adds Dominik Fässler to AUTHORS
Merge branch 'aguinet/master'
Merge branch 'djmitche/heartbeat'
Adds Dustin J. Mitchell to AUTHORS
Fixes for #30

- Sent back the negotitated heartbeat interval in tune_ok

- Made `server_heartbeat` and `client_heartbeat` attributes of the class
  so that they are not dynamically created.

- Renamed `heartbeat_interval` -> `heartbeat` for backwards compatibility.
Remove additional Py2.5 compatibility checks
Funtests passing
flakes
Bumps version to 1.4.0 and updates Changelog
Fixes header in Changelog
Make sure exchange auto_delete deprecation warning is visible.  Closes celery/kombu#296
Fixes heartbeat and NoneType error.  Closes celery/celery#1790
Bumps version to 1.4.1 and updates Changelog