Add utility to support json serialization/deserialization with JSONBigInt

[bhufmann]

The deserialization of TSP JSON strings to class objects that contains bigint fields are done using searialization and a so called Normalizer. This make sure that for example, timestamps are deserialized as bitint and not Number if they are small values.

It would be good to provide a utility that supports this for non-TSP classes.

[marco-miller]

@bhufmann, may we close this issue, told as having been fixed by this commit?

[bhufmann]

@bhufmann, may we close this issue, told as having been fixed by this commit?

That commit is still in my fork of the repository and hasn't been mainlined. Re-opening this Issue.

[marco-miller]

@bhufmann, may we close this issue, told as having been fixed by this commit?

That commit is still in my fork of the repository and hasn't been mainlined. Re-opening this Issue.

Thanks, didn't notice the fork branch; sorry for the hassle. Noted.