BUG: Register AzimuthElevationToCartesianTransform to factories.

ITK-2953.

Change-Id: If4f2e99b9ab024d7d70e1c79717333dcd815e801
Merge topic 'AzimuthTransformRegistration'

854be838 BUG: Register AzimuthElevationToCartesianTransform to factories.