v1.2.1

This is a "patch" release for the VERS specification to capture a set of updates from the final review cycle for ECMA-xxx-VERS 1st Edition.
The normative content was approved for submission to the Ecma General Assembly at its December meeting.

See https://ecma-tc54.github.io/ECMA-xxx-VERS/ for the final draft.

What's Changed

• Remove reference to ECMA-262 by @mjherzog in #141
• Update Validation Rules by @mjherzog in #144
• Add clarification that 1st edition does not support tree-based versioning by @mjherzog in #145
• update schema version by @mjherzog in #148
• Reorganize VERS test schema documentation by @mjherzog in #149

Full Changelog: v1.2.0...v1.2.1