This should obsolete the delta support in makepkg. Having a separate script
should be more flexible.
Example usage:
$ pkgdelta repo/tzdata-2009a-1-x86_64.pkg.tar.gz repo/tzdata-2009b-1-x86_64.pkg.tar.gz
==> Generating delta from version 2009a-1 to version 2009b-1
==> Generated delta : 'repo/tzdata-2009a-1_to_2009b-1-x86_64.delta'
Signed-off-by: Xavier Chantry <shiningxc@gmail.com>
