DefaultOptionsV1 is the set of all options that define default v1 behavior.

DefaultOptionsV2 is the set of all options that define default v2 behavior.

GetUnknownOption is injected by the "json" package to handle Options declared in that package so that "jsonopts" can handle them.

JoinUnknownOption is injected by the "json" package to handle Options declared in that package so that "jsonopts" can handle them.

Struct is the combination of all options in struct form.

Options is the common options type shared across json packages.