Patch Improvements
- Fix gc error log: avoid AttributeError in _unregister_cleanup (dpkp PR 747)
- Wakeup socket optimizations (dpkp PR 740)
- Assert will be disabled by "python -O" (tyronecai PR 736)
- Randomize order of topics/partitions processed by fetcher to improve balance (dpkp PR 732)
- Allow client.check_version timeout to be set in Producer and Consumer constructors (eastlondoner PR 647)