allow multiple versioning strategies simultaneously

I'm working on an application where one of the API consumers uses JSONP, which isn't able to pass additional headers. 

The "preferred" way of accessing the API is to pass the version number as a header, but I also need to support either path or parameter methods for the JSONP to work. The original code made the various methods mutually exclusive. I made some very minor changes to allow multiple strategies.

All the specs still pass, as well as my own production specs. Do you feel strongly about not allowing multiple options, or is this a change you might consider?

Thanks!