Enable Gunicorn max_requests config through env

This commit enables a user to alter the `max_requests` parameter
passed through to Gunicorn without having to resort to the "bare"
CMD-specification hinted at in the Advanced documentation.

Author: thieman

contrib/gunicorn_config.py

@@ -12,7 +12,7 @@
 graceful_timeout = int(os.environ.get('GUNICORN_GRACEFUL_TIMEOUT', 3600))
 timeout = int(os.environ.get('GUNICORN_SILENT_TIMEOUT', 3600))
 worker_class = 'gevent'
-max_requests = 100
+max_requests = int(os.environ.get('GUNICORN_MAX_REQUESTS', 100))
 workers = int(os.environ.get('GUNICORN_WORKERS', 4))
 log_level = 'debug'
 debug = True