Use indicator-messages for persistent notification

If you miss the notification there is no indication that timer's time has elapsed. A simple indication with indicator messages would be nice. Evolution alarms use that.

Workflow:
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A) When timer's time elapses, it creates a simple notification in the indicator. And indicator-messeges turns blue.

B) When user click the message it simply bring app in focus. The notifications from indicators are removed automatically.

Messeging-Menu API:

https://developer.ubuntu.com/api/devel/ubuntu-13.10/python/MessagingMenu-1.0.html#MessagingMenu.Message

A simple example:

http://bazaar.launchpad.net/~indicator-applet-developers/indicator-messages/trunk.16.10/view/head:/libmessaging-menu/client-example.py