Updated notification to have a timestamp instead of an ID.

AFDP-101
Created a command to update a fixture's status.

AFDP-101
Created an abstract notification implementation.

AFDP-101
Implemented a status change notification.

AFDP-101
Changed the status change notification fields and renamed it.

AFDP-101
Added missing package info.
Created a mock service to generate event notifications (for testing).

AFDP-101
Plugged in a test notification to update the client's fixture status.

AFDP-101