Preliminary updates to Makefile. The following changes were made:
* shadow-utils, libpng and ghostscript were descriptsified, as the
patches we added were fixed in upstream. In particular, see:
http://pkgs.fedoraproject.org/gitweb/?p=shadow-utils.git;a=commit;h=e772ed6ecf59a7e90a3ecf6953676e03e00a7951
http://pkgs.fedoraproject.org/gitweb/?p=libpng.git;a=commit;h=7698ae05180c8526550413a153933cd594dcd3e3
http://pkgs.fedoraproject.org/gitweb/?p=ghostscript.git;a=commit;h=33c4fe6c8ba1c7dd71d84a7213a375d3530930fb
* Fedora 12 s/i586/i686/, see http://fedoraproject.org/wiki/Features/F12X86Support#Summary
* Mock environments updated (relevant /etc changes not committed yet)
* Sketchy readline RPM temporarily punted; we'll need to bring it
back later.
