Use Voigt avarage in MS_interpolate
Use Voigt avarage in MS_interpolate

We should probably avoid the complication
of taking the inverse.

alanfbaird/MSAT,jwookey/MSAT,alanfbaird/MSAT,pusher96/MSAT,pusher96/MSAT,pusher96/MSAT,jwookey/MSAT,jwookey/MSAT,alanfbaird/MSAT