added writer mixin
added writer mixin

PiJoules/Septa-Notifier,PiJoules/PhillyCodeFest2016,PiJoules/PhillyCodeFest2016,PiJoules/Septa-Notifier,PiJoules/Septa-Notifier,PiJoules/Septa-Notifier,PiJoules/PhillyCodeFest2016,PiJoules/PhillyCodeFest2016