JsonCpp is one of the package requested for latest cmake.
JSON is a lightweight data-interchange format. It can represent numbers,
strings, ordered sequences of values, and collections of name/value pairs.
JsonCpp is a C++ library that allows manipulating JSON values, including
serialization and deserialization to and from strings. It can also
preserve existing comment in unserialization/serialization steps, making
it a convenient format to store user input files.