GcmEx.Notification
Notification payload
Reference
https://developers.google.com/cloud-messaging/http-server-ref#notification-payload-support
Summary
Types
t :: %GcmEx.Notification{badge: term, body: term, body_loc_args: term, body_loc_key: term, click_action: term, color: term, icon: term, sound: term, tag: term, title: term, title_loc_args: term, title_loc_key: term}