[samba] collect additional files

Add some additional files to the samba plugin and switch from
collecting whole directories (e.g. /etc/samba, /var/log/samba) to
collecting individual named files within those directories.

This gives more predictable behaviour and more manageable default
report sizes.

Signed-off-by: Bryn M. Reeves <bmr@redhat.com>
[ovirt] add ovirt-scheduler-proxy logs

Signed-off-by: Bryn M. Reeves <bmr@redhat.com>