HttpServer should return 404 (not 200) plus information for a path with no handler.
HttpServer now allows removal of a Handler.
Fix bug in Directory where remote copy of local node state could make it's way into the local node's directory.
Directory supports dead-node detection plus bug fix for handling of dead remote gossip node.
Updated to support dead-node reporting from Directory.
Bug fix: Peer should remove it's handler when it is stopped. Otherwise it continues to receive requests.