Add crates and check all link info

This branch contains a few updates to the format of the config file:

• Added concept of crate - specifically new crates section, plus crate & slot field for boards entries
• Added support for compactly specifying large number of links
  • Index lists can be embedded in single links entry - e.g:

    linkA_[00-49]:
      from: [dummy1, x0, '0-49']
      to: [dummy3, x0, '00-49']

This branch also:

• Updates link source info to match CSP fields (linked to cms-cactus/core/swatch!72 (merged))
• Updates the VSCode devcontainer setup to include a docker-compose config, so that can easily run link_test FSM runner demo during development