output basic cyclonedx-json
See https://cyclonedx.org/docs/1.5/json/ for a human readbable version of the schema.
This is the simplest format, but already good enough to use with tools such as https://github.com/DependencyTrack/dependency-track or https://github.com/intel/cve-bin-tool .
Also introduce argparse now that we start to have complex arguments.