res_pjsip/AMI: add contact.updated event

With the old SIP module AMI sends PeerStatus event on every
successfully REGISTER requests, ie, on start registration,
update registration and stop registration.

With PJSIP AMI sends ContactStatus only when status is changed.
Regarding registration:
on start registration - Created
on stop registration - Removed
but on update registration nothing

This patch added contact.updated event.

ASTERISK-25904

Change-Id: I8fad8aae9305481469c38d2146e1ba3a56d3108f