isc_cfgmgr_foreachnodes/foreachproperties enable to list each direct
sub-nodes/properties form within a node.
This is needed in general, and will make it easier to have a dump API
which also will be needed to make materialization testing easier.
The implementation is not great because it's likely slow (lot of LMDB
lookups and string manipulation). But at least it enables to expose the
API so we can built up on top of it, and come back to a better
implementation later.
Colin Vidal
148a6abbc2