Support Docker commands

[mserranom]

Currently the execution environment doesn't support running docker commands against a docker daemon.

Potentially we can use a local Docker daemon and add support as described in Run Docker commands in Bitbucket Pipelines

[SKalt]

I'm considering Would you be open to using dockerode ? It seems like the quickest, best-supported way to build out managing multiple docker processes.

[mserranom]

Thanks, will have a look!