SWITCHYARD-366 Not doing autoboxing for primitive types

Check to make sure in Invocation.java that we provide an exception for unboxing when we test whether the types match the method.     Most of the primitive types are handled by Camel type converters in core CamelMessage.getBody().     For some reason, Character->char conversions are not handled there, so adding a default transformation for that.     

If we want to provide transformations for all the primitive types, I can go ahead and resubmit with the added transformations.     As long as a transformation is provided, CamelMessage.getBody() will use that path.