Cosmetics
AsynPool: -Ofair should not always schedule writes
Pool.flush may not exist
Log message "Skipping revoked tasks" is now "Discarding*" and is info instead of warn
Improve whatsnew
AsynPool: Make sure late terminated task is acked
Tests passing
Version 3.1.0
BROKER_FAILOVER_STRATEGY missing .. setting:: ref (Issue #1620)

The release tool complained::

<pre>
    ---> pavement.verifyconfigref
    PYTHONPATH=. /Users/asksol/.virtualenvs/def/bin/python extra/release/verify_config_reference.py             docs/configuration.rst
    Error: found undocumented settings:
    * BROKER_FAILOVER_STRATEGY
</pre>
Update CONTRIBUTORS.txt