Always re-exchange certs on new kscope ads because the remote peer is likely in a new session and consider JIDs of peers according to their base and not specific resource when checking for equality of proxies -- this allows new kscope ads to override any old entries for the same proxy that should be considered stale #1594
Changed to not add the same listener multiple times in response to multiple connect attempts
Changed to replace existing proxyholders when newer kscope ads come in from remote peer proxies that have likely restarted #1594
Merge pull request #1650 from getlantern/1594

Fixes for cert exchanges closes #1594