split concourse env

[mlilien]

currently the concourse environment is a jack of all trades device. it starts minio, registry and git server as hard dependency. furthermore another env is not easily integratable. if i need e.g. an artifactory in my concourse pipeline, i can not reference it easily from another env.

proposal:
split concourse env and and use a named network that can be used by other env as well.

[mlilien]

Splitting is prepared: named network is provided and the conan artifactory can be used as guide to split the existing concourse environment.
This issue is not finished though.