Would it be possible to create a version of shyaml/shjson that manipulated key-value pairs? E.g.: ``` sh $ echo '{"a": 1, "b": 2}' | shjson put-value c 3 { "a": 1, "b": 2, "c": 3 } ``` or ``` sh $ echo '{"a": 1, "b": 2}' | shjson put-value b 7 { "a": 1, "b": 7 } ``` ?