A Java library that implements application/problem+json
https://github.com/zalando/problem/compare/0.22.0..0.23.0
https://github.com/zalando/problem/compare/0.21.0..0.22.0
https://github.com/zalando/problem/compare/0.20.3..0.21.0
https://github.com/zalando/problem/compare/0.20.2..0.20.3