The overload of afw::image::makeWcs that takes crval, crpix, and CD matrix elements calls the TanWcs constructor with many arguments defaulted, which can lead to incorrect results with older WCSs.

It should probably also just return shared_ptr<TanWcs> instead of shared_ptr<Wcs>, since it always returns a TanWcs.

The implementer of this ticket will undoubtedly also be frustrated by the fact that Wcs returns its CoordSystem via an enum but wants a string when it is constructed, and there's apparently no way to get the right string from an enum value. I'm hoping this can be addressed one way or another on this ticket as well.