[[ ExternalsApiV5 ]] Refactored type mapping to use simple objects.
[[ ExternalsApiV5 ]] Reworked variant generation to handle direct java bindings.
[[ ExternalsApiV5 ]] Added support for using c, objc or java for handler mappings.
[[ ExternalsApiV5 ]] Added support for 'not supported' error when handlers are mapped to 'none'.