Move NotificationManager to new package & rename to Client
Notification v2 base.
Notification v2 implement (un)registerDevice.
Notification v2 implement (un)registerUser.
Notification v2 implement (un)registerUser & refactoring.
Notification v2 implement RequestHelper
Notification v2.
DRY
Rename method
Return single Header
Merge pull request #21 from okaymak/master

Notification v2