Docker container doesn't run diva by default

[rofrano]

The current Dockerfile has no ENTRYPOINT or CMD so it does nothing by default. The whole purpose of packaging a command line tool in a Docker container is to run it. Having it run by default might make it easier for people to use if they don't have to know the command and it's parameters (specifically since the parameters are fixed and not optional).

I propose that we add the following to the Dockerfile:

WORKDIR /diva-distribution/bin
ENTRYPOINT [ "bash" ]
CMD [ "./diva", "/app"]

That will allow users to invoke it with:

docker run --rm \
  -v <path to source code folder>:/app \
  -v $(PWD)/diva-distribution/output \
  diva

This will place the output in the current working folder and simplifies working with DiVA as a command line tool.