Various networking fixes for v0.2 (#789)

* Upgrade to latest ping code

* Use separate method in topology for listened addrs

* Use separate method in topology for listened addrs

* Upgrade to latest libp2p

* Don't add remote ports to topology

* Don't report the protocol isn't open error

* Better notify the task in the handler

* Better score adjustements in topology

* Fix panic when node is replaced

* Don't include backed-off nodes in addrs_of_peer

* Only add to kbuckets when we open substrate

* Minor comment fix

* Some adjustements to ping in the node handler

* Update libp2p

* Start the ping timeout when opening the ping substream