Serveral changes after comments from Steven Dake.
Serveral changes after comments from Steven Dake.

- removed the RHEL distribution support for the review process.
- removed BuildRoot header and %clean section.
- fixed ovirtguest user creation.

Change-Id: I2ebc745ae10ee34caaeec9a17cecc2a10c089cfa

edwardbadboy/ovirtagent-ubuntu,edwardbadboy/ovirtagent-ubuntu,edwardbadboy/ovirtagent-ubuntu,oVirt/ovirt-guest-agent,oVirt/ovirt-guest-agent,silenceli/oga-windows,oVirt/ovirt-guest-agent,silenceli/oga-windows,silenceli/oga-windows,silenceli/oga-windows,edwardbadboy/ovirtagent-ubuntu,oVirt/ovirt-guest-agent