conn.log now sets a field indicating all the parent tunnel UIDs over
which a connection operated and cross reference the UIDs found in
the tunnel.log.
Also some renaming of tunnel related types at the scripting layer.
UDP tunnel support removed for now, to be re-added in specific
analyzers later, but IP-in-IP is now decapsulated recursively
so nested tunnels can be seen and the inner packets get sent
through the IP fragment reassembler if necessary.
