Make timestamp in consistent format after loaded from database

Notification timestamp is generated in MW format (YYYYMMDDHHMMSS)
inside the model and saved to the database in db specific format,
We need to convert it back to MW format when loading the data
from the database, it just happens that MW format is the same
as MySQL timestamp format

Change-Id: Ie881b66c8c24d57a8933c0153e9e7db5fe6aa017