Add a sync flag to full, lazy, passthrough, direct to repository table

[sbluhm]

schema/spacewalk/common/tables/rhnContentSource.sql
add flag to separate table?

[sbluhm]

full = old behaviour
lazy = cache on demand
passthrough = act like a proxy
url = download directly from the given URL
clientrepo = use public repos (requires disabled pillar mgr_disable_local_repos: False https://www.uyuni-project.org/uyuni-docs/en/uyuni/client-configuration/repositories.html)