Site-wide notification messages

[jedateach]

Users should be notified about things important to them, eg:

• Price changes
• Product(s) in cart no longer available, or out of stock etc
• Specials
• Order status updates

These messages should show to the user on the next request made, and therefore the message will need to be available from the site template. Messages should not clear until they have been rendered (read), or dismissed (press X, or "dismiss").

Rather than the system checking various conditions every request, it would be good for the system to push new notifications to customers.

[jedateach]

This could probably be implemented in its own SilverStripe module.

Related: http://addons.silverstripe.org/add-ons/sheadawson/silverstripe-zenmessage