upgrade-juju from 2.0.0 to 2.0.1 failed

[George Kraft]

Using 2.0.1 client on MAAS.

Originally bootstrapped on Juju 2.0-rc2 and have upgraded a number of times via `juju upgrade-juju`.

When we tried to upgrade from 2.0.0 to 2.0.1 with `juju upgrade-juju -m controller`, the command seemed to be successful; however, the controller agent does not appear to have been upgraded.

On the controller machine:

$ sudo cat /var/log/juju/machine-0.log | grep -i "running jujud"
2016-10-03 15:23:48 INFO juju.cmd supercommand.go:63 running jujud [2.0-rc2 gc go1.6.2]
2016-10-12 20:42:58 INFO juju.cmd supercommand.go:63 running jujud [2.0-rc3.1 gc go1.6.2]
2016-10-14 16:41:13 INFO juju.cmd supercommand.go:63 running jujud [2.0.0.1 gc go1.6.2]

It appears the 2.0.1 tools were not copied in:

$ ls -1 /var/lib/juju/tools
2.0.0.1-xenial-amd64
2.0-rc2-xenial-amd64
2.0-rc3.1-xenial-amd64
machine-0

If we try to run the upgrade-juju command again, we get an error:

$ juju upgrade-juju -m controller
ERROR unexpectedly bad version "2.0.1.1-zesty-amd64" in tools storage: unknown OS for series: "zesty"

This message is being spammed in the attached controller logs as well. The controller is running xenial.