added an option to hide notifications.

git-svn-id: http://notifications-widget.googlecode.com/svn/trunk@218 21922344-3934-ee51-d6e3-fd981ce84c01
added an option to hide notifications. (bugfix)

git-svn-id: http://notifications-widget.googlecode.com/svn/trunk@219 21922344-3934-ee51-d6e3-fd981ce84c01