[Feature] Add docker for easier and more reliable local development

[TimidRobot]

Problem

Jekyll / Ruby is difficult to get right across everyone's local development environment.

Description

Use Docker (Docker Compose) so the site can be run locally in a container.

See the creativecommons/cc-resource-archive for an example.

Implementation

• [ ] I would be interested in implementing this feature.

[Silvia-Wachira]

Hi @TimidRobot @possumbilities Could I please get a review on this?