script for checking repo content

The script queries the repository passed as argument outputting
a sorted list with the last version of every package available for
x86_64 (including iX86) and ppc64 architectures.

You can compare the ouput of the command with the one from
a reference repository using for example meld.

Change-Id: Iecb930e74a19c5af1d1a583d280407ba2b66b634
Signed-off-by: Sandro Bonazzola <sbonazzo@redhat.com>