for individual WDs, existence of filters in MSRGB models is not an issue and shouldn't be checked

[tedvh]

We currently do not allow mpiMcmc to run on a file if the filters are not available in both the main sequence + red giant isochrones and the Bergeron WD atmospheres files. This makes sense for clusters, but it doesn't make sense for single WDs where the only issue is whether the filters exist in the Bergeron files. In these cases, the MSRGB isochrones are only used to determine the time a star spends on the main sequence + RGB, which is a function of its mass and metallicity, and not its photometry. I believe this would just require changing the if/then code that allows runs with certain models sets and would not require any recoding anywhere else. This would allow us to run SDSS filters with YY models, for instance.