Raw data number of groups in preprocessing_info has a filtered count

[acesnik]

Is your feature request related to a problem? Please describe.
In loading, there is a filter for rows that have only zeroes after loading the raw values, but the ds.preprocessing_info value 'Raw data number of Protein Groups' reports the count of rows after that filtering.

Describe the solution you'd like
ds.preprocessing_info should report the 'Raw data number of Protein Groups' before filtering only-zero rows, and there should be an additional value (something like 'Raw data number of Protein Groups after removing proteins with only zero intensity') with the filtered count.

[JuliaS92]

This is fixed on the development branch and will be in the next release.