packaging/release updates

[Brian Warner]

Just a quick note to let everyone know where we are with the release:

This morning Daira and I managed to finally land the #1582
"zetuptoolz-ectomy" branch. Zetuptoolz (and the funky code that
surrounds it) provided a custom virtualenv-like scheme. We built it
nearly a decade ago, and we've been trying to get rid of it for over
half of that time. Today it finally shook the hand of /dev/null and went
quietly into that dark night. There was much rejoicing.

The new scheme is just plain tox. Everything installs with pip. Run it
in a virtualenv.

Of course, the buildbot needed to be completely reconfigured, and the
fallout from that is still settling. The main linux builder is green,
but we're having lingering problems with some of the other ones:

* OS-X: the .pkg generation needs to be completely overhauled; it turns
  out it depended upon that bespoke virtualenv scheme, and the packages
  are currently completely broken. I'm poking at it.

* slackware: the "slackhorse" buildslave managed to run out of disk
  space. I think it'll probably work once that's fixed.

* openbsd: Kyle's buildslave is showing some weird C symbol error with
  libssl.so . I'd love it if someone familiar with OpenBSD could take a
  look at

https://tahoe-lafs.org/buildbot-tahoe-lafs/builders/Kyle%20OpenBSD%20amd64/builds/146/steps/tox/logs/stdio

* windows: Daira's buildslave is showing a weird vcvarsall path error
  that I don't understand in the slightest.. maybe some environment
  variable that isn't set correctly? However appveyor is building things
  and passing tests properly. We don't have windows packages yet; those
  might require an overhaul too, I don't know yet.

We need to fix these packaging issues before we can release. We also
have a number of docs that need updating (to reflect the new build
instructions). I've made a start at this, but I think it still needs a
couple of days of editing and feedback. I'm hoping that by the end of
the week, we'll have the first alpha tagged, and folks can try out and
discover what new exciting problems we've introduced. If the packaging
stuff doesn't take forever, that means we might get a release out by the
end of the month. It's likely to be named "1.11" instead of "1.10.3",
since the build changes are pretty significant.

Also, I've agreed to resume command of the release train. Did you know
that you can't steer a train? It only goes forwards. Or stops. Or slides
backwards into unsuspecting other trains. I'll try to make it keep
moving forwards.

cheers,
 -Brian