Further separating the two specs by pointing to bolt08 for transport
details and deduplicating some of the information. Also fixed some
markup while I'm at it :-)
So far we had both the transport layer, with its initialization details,
and part of the base protocol, with some generic messages like `init`
and `error` in a single spec. I propose we split the spec into two, one
for the transport layer and one for the communication on top of that
layer. This should make the independence of the two layers even clearer.
This commit is the first step towards that goal and simply moves blocks
of text into the new spec file. It should not change any semantics.
