The webapp's wormhole pairing almost worked perfectly on the first test.
Turned out the remotedaemon was not noticing that the tor hidden service
got enabled. After fixing that, it worked perfectly!

So, I've merged that feature, and removed XMPP support from the assistant
at the same time. If all goes well, the autobuilds will be updated soon,
and it'll be released in time for new year's.

Anyone who's been using XMPP to keep repositories in sync will need to
either switch to Tor, or could add a remote on a ssh server to sync by
instead. See
<http://git-annex.branchable.com/assistant/share_with_a_friend_walkthrough/>
for the pointy-clicky way to do it, and
<http://git-annex.branchable.com/tips/peer_to_peer_network_with_tor/> for
the command-line way.