Add support of DOCKER_API_VERSION env variable

[Matzz]

No description provided.

[GordonTheTurtle]

Please sign your commits following these rules:
https://github.com/moby/moby/blob/master/CONTRIBUTING.md#sign-your-work
The easiest way to do this is to amend the last commit:

$ git clone -b "master" git@github.com:Matzz/docker-py.git somewhere
$ cd somewhere
$ git commit --amend -s --no-edit
$ git push -f

Amending updates the existing PR. You DO NOT need to open a new one.

[little-dude]

I'd like to have that. Are you planning to finish this up @Matzz / @onzo-mateuszzakarczemny ? Otherwise can I pick it up?

[TomasTomecek]

the description doesn't seem right

[onzo-mateuszzakarczemny]

I'd like to have that. Are you planning to finish this up @Matzz / @onzo-mateuszzakarczemny ? Otherwise can I pick it up?

Hi. Sorry I forgot about this PR. I had some issues with make it working and did some workaround instead of finishing that.
Feel free to pick it if you want.

[ulyssessouza]

@little-dude Are you interested in fixing this? (Or anyone else)
For that you just need to rebase with master to make it pass the CI and fix the comment as suggested by @TomasTomecek in Please rebase the PR with master to make it pass the CI