Provide default modules that may be overrided easily. Previously the
server would load a set of default modules, but only if none were
specified in the xorg.conf, or if you didn't have a xorg.conf at all. This
patch provides a default set and you can add only the "Load" instructions
to xorg.conf that you want without losing the defaults. Similarly, if you
don't want to load a module that's loaded by default, you can add "Disable
modulename" to your xorg.conf (see man xorg.conf in this release for
details). This allows for a minimal "Modules" section, where the user only
need specify what they want to be different. See bug #10541 for more.

The list of default modules is taken from the set loaded by default when
there was a xorg.conf containing no "Modules" section.

A potential problem for some users is that some users disable a module,
most notably DRI, by commenting out the "Load" line in their xorg.conf.
This needs to be changed to an uncommented "Disable" line, as DRI is
loaded by default.