Add RUO calibrations to the VA-Spec output

[afrubin]

Downloaded pathogenicity statements do not include all calibrations, but I think that the ExCALIBR calibration should be included. Including this in the vignette examples would also help highlight the use of the RUO fields and also demonstrate the flexibility of having calibrations with inferred abnormal/normal classes (no separate EvidenceLine for the range) as described in the updated VA-Spec vignette.

[bencap]

We should ensure all RUO calibrations are included in VA-Spec output, however only non-RUO calibrations should contribute to the pathogenicity proposition.