Added ENV DOCKER_IN_DOCKER to fix SSH conn info

[QueerCodingGirl]

This fixes #46 for my docker-in-docker gitlab runner setup.

[codecov]

Codecov Report

Merging #51 (07f3956) into master (b47d868) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master      #51   +/-   ##
=======================================
  Coverage   84.82%   84.82%           
=======================================
  Files           1        1           
  Lines         290      290           
=======================================
  Hits          246      246           
  Misses         44       44           

Impacted Files	Coverage Δ
lib/beaker/hypervisor/docker.rb	84.82% <100.00%> (ø)

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[ekohl]

@h-haaks does #46 (comment) imply you've tested this? If so, can you approve this PR?

[h-haaks]

@ekohl I have tested this branch in our Jenkins setup ( docker in docker ) and locally ( plain docker ) and confirm that it solves #46.
The new env var DOCKER_IN_DOCKER needs to be documented i guess.

[h-haaks]

I don't think I'm allowed to approve PRs ...

[ekohl]

Now it's a bit of bookkeeping (and the current comment is sufficient), but for the record, any logged in user is able to go to https://github.com/voxpupuli/beaker-docker/pull/51/files and use the Review changes button to approve. If you don't have permissions, then it'll show up as gray, otherwise as green.

[ekohl]

I'd be OK with merging this, but I do agree this part would be nice to fix:

The new env var DOCKER_IN_DOCKER needs to be documented i guess.

[QueerCodingGirl]

@ekohl could you merge and release this, please? I added a little bit of documentation.

[ekohl]

Thanks!

[QueerCodingGirl]

@ekohl when is the next release planned, or could you just craft a new release right now? I really dislike having to use my fork at the moment.

[ekohl]

We don't really plan releases. They go out as needed. I think we can prepare one.

[ekohl]

It went out via #57. Thanks for your contribution!