Upgrade django-waffle to 0.11.1
Upgrade django-waffle to 0.11.1

Fixes #893

Mariatta/pythondotorg,manhhomienbienthuy/pythondotorg,Mariatta/pythondotorg,manhhomienbienthuy/pythondotorg,python/pythondotorg,Mariatta/pythondotorg,proevo/pythondotorg,python/pythondotorg,manhhomienbienthuy/pythondotorg,python/pythondotorg,proevo/pythondotorg,manhhomienbienthuy/pythondotorg,Mariatta/pythondotorg,proevo/pythondotorg,python/pythondotorg,proevo/pythondotorg