Code review comment for lp:~thumper/juju-core/fast-lxc-no-apt-upgrade

Reviewers: mp+210536_code.launchpad.net,

Message:
Please take a look.

Description:
Use lxc clone on trusty

This branch speeds up lxc containers for the local
provider only by creating a template as needed that
persists between environments, and this template is
then used as a basis for the machines created in the
environment using lxc-clone.

If /var/lib/lxc is a btrfs filesystem, the containers
use btrfs snapshots. If not, the containers are
created using aufs snapshots.

In addition to this, the apt-get update/upgrade step
is skipped during cloud-init for the cloned machines.

Since the testing required a go routine to shut down
the template container, the mock containers had to be
made go routine safe for the state checking.

Certain extra info was also added for the mock containers,
being the config file and console log.

https://code.launchpad.net/~thumper/juju-core/fast-lxc-no-apt-upgrade/+merge/210536

Requires:
https://code.launchpad.net/~thumper/juju-core/update-golxc-version/+merge/210492

(do not edit description out of merge proposal)

Please review this at https://codereview.appspot.com/74370044/

Affected files (+485, -46 lines):
   A [revision details]
   A container/lxc/clonetemplate.go
   M container/lxc/lxc.go
   M container/lxc/lxc_test.go
   M container/lxc/mock/mock-lxc.go
   M container/userdata.go
   M provider/local/environ.go
   M worker/provisioner/lxc-broker_test.go