So "tahoe create-node --hide-ip" causes "reveal-IP-address = false" to
get written into tahoe.cfg . This also changes the default tahoe.cfg to
include "reveal-IP-address = true", for clarity.
refs ticket:1010
This removes the section that describes automatic configuration using
transport-agnostic endpoint-centric tub.port strings. That was the
approach where tub.port used "onion:80:hiddenServiceDir=PATH", and
Foolscap was able to query the generated Listener to find out what
address it was supposed to advertise. We considered this for a long
time, but in the end decided to use a more static approach, where
foolscap/tahoe never try to guess it's location: Tahoe always requires
tub.location= to be set.
When we get automatic configuration implemented, it'll be a simple CLI
argument, something like "tahoe create-server --listen=tor".
Instead, this document now explains how to configure Tor to create the
hidden service, then how to copy the generated .onion address into the
tahoe config.
This also removes a lot of other text that seems irrelevant now, and
refers the user to the tahoe.cfg docs (configuration.rst) instead of
including all the `[tor]`/`[i2p]` docs inline.
Closes ticket:2815
