The #[global_allocator] attribute is not available in versions prior to
1.28.0, the default-linker-libraries feature requires rust 1.31.0.

Adapt the CI to prevent accidental increases in Rust version by testing
against 1.31.0, beta and nightly.

"ours" to avoid version bump.

Signed-off-by: David Goulet <dgoulet@torproject.org>

New IP address from 194.109.206.212 to 45.66.33.45.

Signed request from Alex de Joode, operator of dizum:
https://trac.torproject.org/projects/tor/ticket/31406



Published descriptor by dizum on August 12th, 2019:

--
r dizum fqbq1v2DCDxTj0QDi7+gd1h911U GZmZtCLaPDQNxkhIFj8UcgTRAuA 2019-08-12 15:28:40 45.66.33.45 443 80
s Authority Fast Running Stable V2Dir Valid
v Tor 0.4.0.5
pr Cons=1-2 Desc=1-2 DirCache=1-2 HSDir=1-2 HSIntro=3-4 HSRend=1-2 Link=1-5 LinkAuth=1,3 Microdesc=1-2 Relay=1-2 Padding=1
w Bandwidth=20 Unmeasured=1
p reject 1-65535
--

Finally, confirmed by DNS:

  $ dig +short tor.dizum.com
  45.66.33.45

Closes #31406

Signed-off-by: David Goulet <dgoulet@torproject.org>

Closes bug 31418.

Also document the other log changes in this branch.

By binding the protover numbering to specific padding machines, we can make
our padding negotiation simpler. We probably should have done this in the
first place.

This has the side effect that earlier 0.4.1.x-alpha clients won't negotiate
with 0.4.1.x-stable relays, and 0.4.1.x-stable clients won't negotiate with
earlier 0.4.1.x-alpha relays (or 0.4.0.x relays). Since we don't support
alphas after the stable is released, this is fine, so long as it gets in
before the first stable of 0.4.1.x.

This can happen, it's not great, but it's not the worst thing in the world
either. Deferring full fix for 0.4.2/later.

Also add controller circuit id to all relevant circpad loglines. This will
make debugging any future issues like #30992 much easier.