Removed custom implementation of CalledProcessError
Removed custom class of CalledProcessError which was required for
Python versions prior to 2.5
Fixes: https://fedorahosted.org/freeipa/ticket/5717
Signed-off-by: Abhijeet Kasurde <akasurde@redhat.com>
Reviewed-By: Petr Spacek <pspacek@redhat.com>