[LightDM] Setting default X session

[Guido Berhoerster]

Hi,

just FYI, instead of using lightdm-set-defaults to set the
default greeter I'm using update-alternatives to manage the
default greeter. This works by compiling LightDM with
--with-greeter-session=lightdm-default-greeter and having update
alternatives manage a
/usr/share/xgreeters/lightdm-default-greeter.desktop symlink.
Greeters now only need to be cooperative and register themselves
with update-alternatives. This ensures predictable behavior,
allows users to override the default in lightdm.conf or via
update-alternatives and also makes sure that there is always a
valid greeter specified.
-- 
Guido Berhoerster