As part of the final preparation towards the v2 release, this release finalises the use of the new multi-repo packages, and deprecates all internal packages ahead of next week's release removing them.

Key callouts

• Migrate middleware to their own Go modules by @jamietanna in https://github.com/deepmap/oapi-codegen/pull/1257
• Replace + deprecate testutil by @jamietanna in https://github.com/deepmap/oapi-codegen/pull/1314

Full Changelog: https://github.com/deepmap/oapi-codegen/compare/v1.15.0...v1.16.0