Make cargo happy

v0.1.4

Make cargo happy

Correct version number in the built binary

Thanks to advances in the state-of-the-art in package management technology,
and a bit of sed, we no longer have to embed release version numbers in git
commits.

Tweak command-line help

Just a little adjustment to the --help output, so that it's more
obvious that action-validator only takes a single file to check (for now).

Initial Release

I'm pleased to be able to announce the inaugural release of action-validator,
your one-stop shop for not committing hideously incorrect GitHub Action and
Workflow YAML files.