[Fontconfig] Switch to automake

[Keith Packard]

To resolve ongoing problems with library creation on various operating 
systems, and to make the configuration process more consistent with other 
packages, I've replaced the pure autoconf configuration mechanism with 
automake.

Part of this process involved getting a change into libtool that allows 
packages to explicitly specify library version numbers; that should make 
it into libtool 1.5, but for now, I'm simply including a version of ltmain.sh
incorporating this change in the fontconfig CVS.

I'm very interested in hearing of any problems this causes, as well as any 
bugs it fixes.

-keith