* ios: get device token for push notifications
* ios: receive messages when background notification is received
* add notifications API, update simplexmq
* chat API to register and verify notification token
* update AppDelegate to recognize different notification types, update simplexmq
* core: api to enable periodic background notifications
* update simplexmq
* chat API to delete device notification token
* use base64url encoding in verification code
* update simplexmq for notifications
* updated text items
* update version
* fix JSON parsing in CIDirection, refactor data samples
* show group member in received messages and chat preview
* use profile displayName instead of localDisplayName, do not show fullName if it is the same as displayName