Add a DOCKER_API_VERSION env var
Add a DOCKER_API_VERSION env var

Closes: #11486

Just for @ahmetalpbalkan  :-)

Fixed some comment formatting too while in there.

Signed-off-by: Doug Davis <ff3bde741799c0eff815b83a54eda3fc494df54f@us.ibm.com>

rhatdan/engine-api,msabansal/engine-api,vdemeester/engine-api,docker/engine-api,thaJeztah/engine-api,jwhonce/engine-api,mikedougherty/engine-api