- Move site check for prefix4 and extra_prefixes6 to gluon-core, so the
rules don't need to be duplicated in several packages. This also fixes
gluon-respondd not checking extra_prefixes6 at all when
gluon-ebtables-source-filter is not installed as well.
- A redundant check for prefix6 is removed from gluon-l3roamd (this was
already checked by gluon-core)
- A separate check for prefix4 remains in gluon-client-bridge, as the
setting in mandatory there
In addition to significant internal differences in check_site_lib.lua (in
particular unifying error handling to a single place for the upcoming
multi-domain support), this changes the way fields are addressed in site
check scripts: rather than providing a string like 'next_node.ip6', the
path is passed as an array {'next_node', 'ip6'}.
Other changes in site check scripts:
* need_array and need_table now pass the full path to the sub fields to the
subcheck instead of the key and value
* Any check referring to a field inside a table implies that all higher
levels must be tables if they exist: a check for {'next_node', 'ip6'} adds
an implicit (optional) check for {'next_node'}, which allows to remove many
explicit checks for such tables
