Cmdline configuration structure

[mmh352]

The command-line statement is an obvious source of errors syntax wise, and also hard to read and a faff to declare?

web_apps:
  - path: openrefine
    cmdline:
      - /var/openrefine/openrefine-3.3/refine
      - -i
      - 0.0.0.0
      - -p
      - "{port}"
      - -d
      - /home/ou-user/OpenRefine

Cleaner might be to allow a single long line and then split it into tokens on the space character?

Originally posted by @psychemedia in https://github.com/mmh352/ou-container-builder/issues/11#issuecomment-832073779

[mmh352]

The reason for this structure is that it generates a list, which is the exact data-structure that jupyter-server-proxy wants. It also gives full control over how the command is passed to jupyter-server-proxy. However, the option to also provide a string and have that split on white-space is probably sensible.