Please describe the problem.

git annex p2p --gen-address creates an auth token and than immediately prints it out so that it can be used to pair with another machine.

But what am I supposed to do if I want to pair a third machine later? I do not want to call --gen-address again since it probably creates another token or even worse overwrites the token already used for one pairing.

So we lack a command like git annex p2p --show-address that just prints the same as --gen-address. This is trivial since we just need to concatenate .git/annex/creds/p2paddrs, a colon and .git/annex/creds/p2pauth?

Actually this would be a fun starter project for a new contributor to git-annex? (me?)