To replace all calls to deprecated code, GTK+ 2.20 is required - add
some basic compatibility code, so that is still possible to build the
shell with GTK+ 2.18 when not using -DGSEAL_ENABLE.
https://bugzilla.gnome.org/show_bug.cgi?id=618258
With the transition to GTK+ 3.0, direct access to struct members
will no longer be possible.
This bumps the required minimum version of GTK+ to 2.20.
https://bugzilla.gnome.org/show_bug.cgi?id=618258
notification are to the panel. A bit warty, but we don't know how we want
the final UI to look anyway. (The fact that transparency doesn't work is
a known bug.)
svn path=/trunk/; revision=44
