First cut of logger-based statsd
Metrics sent on request and arbiter
Sanitize arguments to not trick regular loggers
Tested with mainline statsd
Drop tracing and sampling to keep the code tight
Merge branch 'master' of https://github.com/benoitc/gunicorn into statsd-logger
More in-depth documentation of the new instrumentation layer
Cosmetic cleanup
Fix: logger_class can be undefined.
Move setting of environmental variables before preload_app start.

Move setting of env vars from Arbiter.start to Arbiter.setup so that they are available during application start up when 'preload_app' is used.

Closes #735
Remove unused imports
Stop all servers
Merge branch 'master' of https://github.com/benoitc/gunicorn into statsd-logger
Incorporate feedback from PR

Use extra keyword in logger, more pythonic
capture response code as a rate metric
Fix silent exception in response code capture
Fix failing test and reorder logging to always log
Use TRAVIS_PYTHON_VERSION to install aiohttp on Python 3.
Merge pull request #781 from berkerpeksag/use-travis-py-version

Use TRAVIS_PYTHON_VERSION to install aiohttp on Python 3.
fix #785: handle binary type address given to a client socket address
Update custom application example.

It's running on both Python 2 and 3 now.