A Rekord can be built from another Rekord.
After building a Rekord from another Rekord, the original does not mutate.
The key of a Rekord property cannot be null.
Stabilised the Rekord::toString test.
Wrote a Hamcrest matcher for the Rekord type.
Use the Hamcrest matcher for all assertions on Rekord values.
Nix some unnecessary whitespace.
All classes must be final.
The value of a Rekord property cannot be null.
Yield better error messages when dealing with nulls.
Properties can be removed from a Rekord.
Rename Rekord.RekordBuilder to Rekord.Builder.
Building two Rekords from the same builder does not cause the first to mutate.