Orange: AlphaGov: not using Travis anymore

Orange specifics:

• bosh-cli-v2-cf-cli
• k8s-tools
• terraform (overrides Alphagov)

Contains Dockerfiles to build docker images for Cloud Foundry tools and other tools we use regularly.

Each directory with a Dockerfile relates to a container and will have repository of the same name in Docker Hub.

You can add a new container you only need to add these files:

• The Dockerfile and support files to build the image.
• A README.md file describing the container
• A workflow to allow building the container. Use one of the existing ones in '.github/workflows/image_*.yml' for reference.
• Optional: a *_spec.rb file to test the container.

Note: The repository must be added to Docker Hub manually

Tasks to build and tests the containers will be generated automatically:

• rake build:bosh-init builds the container under ./bosh-init
• rake build:all builds all containers
• rake spec:bosh-init tests the container under ./bosh-init
• rake spec:all tests all the containers

Travis will execute the tasks build:all and spec:all