This extends the same scenario as before, to scattering from particles

This should test whether a polarized computation engine is correctly used when an analyzer is set, even when a non-magnetic sample is used

Import for reflectometry

Remove dependency from MVVM lib

rm dependency from MVVM lib (only one call so far). Motivation: MVVM dependency causes runtime error on MAC

rm dependency from MVVM lib (only one call so far). Motivation: MVVM dependency causes runtime error on MAC

make loader part of realDataItem; allow native data reset; add unit tests; data loader: cache result; parsing; error handling; load/store