As of e12dbb460 (#1758) we no longer force the usage of pcap when
encryption is enabled. Hence...
- we no longer need to figure out whether the router was started with
a password when re-attaching it from the proxy. We therefore remove
the code for that.
- there is no longer any mode in which we pass both `--datapath` and
`--iface` options to the router. Previously this would only happen
when encryption was enabled and the only overlay used for
connections was sleeve. It is not clear what the behaviour is when
these conditions do not hold, so, to be safe, we prevent the
specification of both flags.
Matthias Radestock
799160c5c2