Validate plugin version numbers

[ewels]

See #110 (comment) - we should add validation of this to the JSON schema for CI.

Would this work @bentsherman ? https://semver.org/#is-there-a-suggested-regular-expression-regex-to-check-a-semver-string

^(0|[1-9]\d*)\.(0|[1-9]\d*)\.(0|[1-9]\d*)(?:-((?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\.(?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\+([0-9a-zA-Z-]+(?:\.[0-9a-zA-Z-]+)*))?$

Though maybe that's too permissive: https://regex101.com/r/RlYsCm/1

Would a simpler one ok?

^(\d+\.)?(\d+\.)?(\*|\d+)(-\w+)?$

(must be a 3-part numeric, with optional hyphen+alphanumerics at the end)

https://regex101.com/r/1fcwZM/1

[tom-seqera]

For reference, the plugin framework used by Nextflow (pf4j) uses SemVer for plugin versions. Specifically, the jsemver library.