XBMC4Xbox

Currently when an alarmclock setting is cancelled, a message pops up notifying user of cancellation. It'd be nice if we can cancel the alarm silently, that is to say, not show the notification message.

We would then use it as follows:
<onunload>CancelAlarm( foo, True )</onunload>

The changes from xbmc can be found at the following link: https://github.com/xbmc/xbmc/commit/ed0544bc436797010160bbbb4f0729f8c03274e3

Thank you for your continued dedication!