Support for Jackson-powered parsing and printing for circe.
Note that not all guarantees that hold for Jawn-based parsing and the default
printer will hold for the Jackson-based versions. Jackson's handling of
numbers in particular differs significantly: it doesn't distinguish positive
and negative zeros, it may truncate large JSON numbers or simply fail to
parse them, it may print large numbers as strings, etc.
The implementation is ported with minimal changes from Play JSON.