[compiz] Include option type in gconf schema

[Mike Dransfield]

>> I have separated all the gconf code in the program into separate
>> wrapper functions so when the dbus changes get into  the head then I
>> should be easily be able to switch the backend to use dbus instead. I
>> think tho there is one option missing with dbus, is there anyway to
>> get a list of plugins available? 
>>     
>
> There's no way to do that through gconf either. You just have to scan
> the directories where compiz searches for plugins.

I think this is possible to do inside the dbus plugin, it does not seem 
straight
forward to locate the correct directory as compiz could have been compiled
in any directory.

Even if it is possible to find the directory, the external developer 
will have
problems because some plugins may be there which will not load.

I _think_ that it will be possible to add a function which will return 
all of
the possible plugins, I can then attempt to load each of the plugins but
not initialize it (only if it is not already loaded).  Once it is loaded 
I can
read the vTable and check the ABIVERSION.  I can then return the
plugins along with the ABIVERSION and whether or not it loaded. 
This will allow you to alert the user to out of date or junk plugins.

If this extra bit takes too long I will send the option metadata patches
(hopefully they can be squeezed in for a 0.3.4 release), and submit
the plugin metadata patches later.  Either way I will try to get something
by the end of the week.