fanatic needs to provide storage option for LXD tests

SRU justification:

Impact: In Zesty (and later) the CLI of LXD changed. There is now a storage command and creating a container expects the storage pool which should be used to be provided via the --pool argument.

Fix: Added a function which returns the first storage pool found by calling "lxc storage list". For older versions of LXD this command fails and returns an error (+ empty string). In that case the "lxc launch" command, which is called later will be used without any --pool option (which is as it was before the CLI change). With this things should work with the old CLI and the new one and regression potential should be low.

Testcase:
 - [with LXD installed and configured]
 - fanatic enable-fan ...
 - fanatic enable-lxd ...
 - fanatic test-local-lxd ...

Hello Stefan, or anyone else affected,

Accepted ubuntu-fan into zesty-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/ubuntu-fan/0.12.2.1 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed.Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, and change the tag from verification-needed to verification-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

This bug was fixed in the package ubuntu-fan - 0.12.3

---------------
ubuntu-fan (0.12.3) artful; urgency=medium

  * fanatic: Prevent error message without docker installed (LP: #1691485)
  * fanatic: Supply LXD storage if needed (LP: #1691490)
  * dep8: Add LXD auto-test

 -- Stefan Bader <email address hidden> Mon, 22 May 2017 14:02:34 +0200

Verification:
- with ubuntu-fan=0.12.2 test-local-lxd fails to bring up a container
- after updating to ubuntu-fan=0.12.2.1 test-local-lxd successfully runs

This bug was fixed in the package ubuntu-fan - 0.12.2.1

---------------
ubuntu-fan (0.12.2.1) zesty; urgency=medium

  * fanatic: Prevent error message without docker installed (LP: #1691485)
  * fanatic: Supply LXD storage if needed (LP: #1691490)
  * dep8: Add LXD auto-test

 -- Stefan Bader <email address hidden> Mon, 22 May 2017 14:01:01 +0200

The verification of the Stable Release Update for ubuntu-fan has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.