a11y stack change

[Matthias Clasen]

Just a heads-up:

As part of the ongoing march towards GNOME3, I have switched the
accessibility stack to default to the dbus stack
(at-spi2-core/at-spi2-atk/pyatspi) instead of the Corba stack (at-spi).

Some initial testing shows that orca and caribou seem to work ok. One
issue that I've noticed so far is that firefox is unwilling to pop up
menus when accessibility is turned on. I am working with the
aeccessibility team upstream to resolve this and other issues that will
no doubt pop up.

If you notice problems that look like they might be related to this
change, please let me know.


Matthias