Support for extended docker configuration in gitlab-ci.yml

What does this MR do?

Adds support for some Docker configuration options set with .gitlab-ci.yml file. Needs gitlab-org/gitlab-ce!8578 to work, because .gitlab-ci.yml is parsed in GitLab CE/EE and then job configuration is send to Runner. This MR adds support for new configuration options available in job's payload.

Why was this MR needed?

Please look into: #1466 (closed), #1421 (closed), #1284 (closed) for reference.

Are there points in the code the reviewer needs to double check?

Does this MR meet the acceptance criteria?

• Documentation created/updated
• Tests
  • Added for this feature/bug
  • All builds are passing
• Branch has no merge conflicts with master (if you do - rebase it please)

What are the relevant issue numbers?

Closes #1466 (closed), #1421 (closed), #1284 (closed)