So far, the Dockerfile built hydrogen on the server running the image,
instead of building it during the building of the image. This blew up
the image size immensely and caused node+yarn to run in the resulting
image. This new Dockerfile builds hydrogen in a separate build stage and
then moves the target directory into an nginx based container image,
which takes care of serving the target webroot.
The existing Dockerfile has been moved to Dockerfile-dev for usage as a
development environment. The docs have been adjusted accordingly.
Additionally, this switched from a fixed alpine version of the node
image to the latest alpine version, and changed the container image
references in the `FROM` statements to use the fully qualified
references including the registry domain.
