add run_shell helper

The new run_shell helper is a copy of run_python,
and will be used by upcoming changes.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
add support for zypp

This adds support for zypper which is used as package management in
SuSE Linux. It started out as copy of yum support.

TODO:
 add regex support

Signed-off-by: Olaf Hering <olaf@aepfle.de>