Importer: selection of pre-defined values vs. excel column

[PavelBal]

Selection of pre-defined entries for the meta-data "Species, Organ, Compartment, Molecule, Gender" seems unintuitive for me. Right know, the pre-defined values (coming from PK-Sim project) can be selected in the "excel column" column of the configuration. I find this confusing and would suggest to only show selectable sheet columns in the "Excel column" column, and show the manually selectable entries in the column "Edit extra fields" (which I would rename to "Manual edit").

If something is selected manually, the entry in the "Excel column" is something like "". If the user actively selects a column after manually selecting an entry, the column is used and the "Manual entry" gets cleared.

@msevestre @Yuri05 @abdelr We can discuss this if you want.

[PavelBal]

Agreed against.