Sets release date for 3.1.10
Tox: Add debug test output
Tox: Set environment variables properly
Make the database backend retry operations on ResourceClosedError and StaleDataError too. Make the operations close the connection if failure occurs (can't retry on broken connection). Fixes #1786.
Don't close the session. Just rollback and/or close.
Close the sessions before disposing the engines as the engines won't close connections held up in sessions.
Use a session manager that has different behavior before the fork (effectivelly hardcodes NullPool - everything else is unreliable).
Update changelog.
Cosmetics for #1736
flakes
Stress test app now loads on Windows
Fix issue with timer starting after stop() is called. Now it doesn't start in this situation.
Match the signature used in the rest of the code.
ColorFormatter should not modify record.msg.  Closes #1939
Yaml is not exception-able
Tests: Make sure all threads get the current app trap
Docs: generic celerybeat options should not write schedule to root owned directory.  Thanks to Nikos Fertakis.
Result cache populated by join_native even if cache disabled
Stresstests: Delete results after bigtasksbigvalue test
Task: Do not send error emails for expected errors (@task(throws=...))