extend focus fix to Kadu
Merge pull request #3215 from d4m/patch-1

extend focus fix to Kadu
cinnamon-settings windows: fix visibility of minimum opacity spinner.
sound applet:  Some fixes to eliminate warnings/errors (and hopefully crashes)
popupMenu.js - Recalculate separator widgets when the allocation of
the menu changes.

Some popup menu actions that don't close the menu upon triggering can
leave the menu in an inconsistent state.  This adds a listener to the
menu's actor, any time a menu item is removed/hidden/shown/added, the
separator widget visibilities are recalculated to make sure no two
separators appear visible adjacent to one another.
Added dependency on gksu (needed by cinnamon-settings-user)