Local docker images are not used by runner - possible regression

Hi,

We have problem with gitlab-ci-multi-runner not using local docker images. Version 0.6 totally ignores docker images which are located(and modified) on local machine. With version 0.5.5(gitlab-ci-multi-runner-0.5.5_1_g69bc9341-1.x86_64) it works like a charm.

Output from GitLab:

Version 0.6:

gitlab-ci-multi-runner 0.6.0 (4c26bc5)
Using Docker executor with image xxxx/centos ...
Pulling docker image xxxx/centos:latest ...
WARNING: Cannot pull the latest version of image xxxx/centos:latest : Error: image xxxx/centos:latest not found
Pulling docker image gitlab/gitlab-runner:cache ...
Running on runner-c8db3ded-project-1-concurrent-0 via xxxx...

Version 0.5.5:

gitlab-ci-multi-runner 0.5.5-1-g69bc934 (69bc934)
Using Docker executor with image xxxx/centos:latest ...
Running on runner-f5ac6250-project-1-concurrent-0 via xxxx...

I suspect following commit which could introduce this regression: https://gitlab.com/gitlab-org/gitlab-ci-multi-runner/commit/dd412406df8192d2f51c504d55eb293c5e3e41bf

Best regards, Mateusz