Implement notification of container updates.
Implement notification of container updates.

All plugins need to do to notify clients of changes in a container,
let's say 'some_container' is to call 'some_container.updated()'.

svn path=/trunk/; revision=612

Pelagicore/Media-Manager-Rygel-patched,GNOME/rygel,GNOME/rygel,Tarnyko/rygel,Tarnyko/rygel,jku/rygel,Pelagicore/Media-Manager-Rygel-patched,luisbg/rygel,Pelagicore/Media-Manager-Rygel-patched,jku/rygel,GNOME/rygel