svc/conntrack: Make the kickpeers coroutine more robust.

svc/conntrack: Make the kickpeers coroutine more robust.

There are inevitable races between where conntrack enumerates the peers
and when it submits the commands to modify the list.  Also, there's no
guarantee that `connect' -- which we use for initiating peer connections
-- is running at all.  So trap exceptions from the relevant commands and
issue warnings as appropriate.