feat: release metadata

[AuHau]

SemVer spec allows to the version contain a metadata about the build using format <semver>+<metadata>. This patch extends the release task with ability to specify metadata to be appended to the version.

This will be used for example in js-ipfs-repo-migrations to give information about what latest migration does the release contain as discussed https://github.com/ipfs/js-ipfs-repo-migrations/pull/1#discussion_r336461176