Added missing import for `platform` in tests/support.py for os x.
Merge pull request #944 from redspade/master

Added missing import for `platform` in tests/support.py for os x.
Use more Pythonic style in gunicorn/.
Fix NameError in gunicorn/workers/gthread.py.
Use `sent` instead of `response_length` in access log

Previously, resp.response_length is used for the b atom of the access
log formatter. If the application does not set a content-length header,
response_length is left as `None`, resulting in b being set to the
fallback "-". resp.sent is a more reliable way to determine the number
of bytes in the response body.
Pass a 'sent' parameter to Mock().
Merge pull request #945 from berkerpeksag/flake8-cleanup

Use more Pythonic style in gunicorn/.
Merge pull request #946 from berkerpeksag/fix-namerror

Fix NameError in gunicorn/workers/gthread.py.