[gnome-flashback] session-shortcuts package in Xenial

[Alkis Georgopoulos <alkisg gmail com>]

Ubuntu has started shipping a new package called "session-shortcuts":
http://packages.ubuntu.com/xenial/session-shortcuts
"Allows you to shutdown, logout, and reboot from dash".

It ships:
/usr/share/applications/logout.desktop
/usr/share/applications/reboot.desktop
/usr/share/applications/shutdown.desktop

These show up in gnome-flashback under the Applications → Accessories menu.
I don't think we want them there.
Maybe we could tell the Unity folks to ship them as [Desktop Action xxx] 
stanzas instead of [Desktop Entry]?