Hide notification icons from statusbar

When long pressing a notification, add another menu item which allows the user to hide
the notification icon while keeping the actual notification in the dropdown

This is meant for applications which have services running
in the statusbar which the user is aware of, so right now
we hide the icon by the package

Credit/Thanks to @romanbb

Change-Id: I41f81255fd835ce1ba661e481529b1def8b0b938