Added documentation for FeedbackService to README
Added documentation for FeedbackService to README

stephenmuss/django-ios-notifications,chillbear/django-ios-notifications,nautilebleu/django-ios-notifications,CrazyNPC/django-ios-notifications,nautilebleu/django-ios-notifications,stephenmuss/django-ios-notifications,nautilebleu/django-ios-notifications,stephenmuss/django-ios-notifications,CrazyNPC/django-ios-notifications,chillbear/django-ios-notifications,CrazyNPC/django-ios-notifications,leotsem/django-ios-notifications,chillbear/django-ios-notifications