+ - If the topology daemon crashes, peers that were put on the
+ blacklist with transport will never be removed from it (until
+ transport service dies); we should use the blacklist notification
+ API to learn about the exact set of blacklisted peers at all times
+ (FIXME: the transport_api implementation of blacklisting
+ also does not work nicely for this since it won't let us know about
+ disconnect-reconnect events and the implicit whitelisting
+ that might happen here; that's not so bad since we will
+ re-blacklist on pre-connect attempts anyway, so this is
+ a minor issue).
+ - the code uses the term 'blacklist' for both peers that are forbidden
+ to connect (i.e. F2F mode) as well as peers that we currently
+ won't try to actively connect to ourselves (since we just tried);
+ This is confusing. We need two distinct terms.
+ - move code to use hash table instead of linked list
+ - instead of periodically discarding blacklisted entries,
+ simply add task that is triggered at the right time (earlier free,
+ more balanced load)
+ - check if new HELLO learned is different from old HELLO
+ before resetting entire state!