packaging: setup: produce and manage setup logs at /var/log

although setup logs are not of daemon, they used to be stored at
/var/log for future reference.

the location of the logs was changed, to improve
/var/log/ovirt-engine sanity.

    /var/log/ovirt-engine -> /var/log/ovirt-engine/setup

A log rotation was introduced in order to compress old logs.

Change-Id: I2b676ce4dd92e450086b16b4311a981b9071060e
Signed-off-by: Alon Bar-Lev <alonbl@redhat.com>