host-deploy: use tar instead of python tarfile

python usage was introduced when fedora-18 alpha lacked tar
utility, now fedora-18 has tar utility and the python
implementation is too buggy. It does not treat trailing
zeros of tarfile correctly, causing the deployment to fail.

Change-Id: I9ece009af7d0c1800eb69b1ca99930892903fe9f
Signed-off-by: Alon Bar-Lev <alonbl@redhat.com>