Selection list values surrounded with spaces are not cleaned when importing

[ifokkema]

When editing an entry, spaces surrounding selection list values are cleaned. When importing, this isn't done. The spaces are removed to match an entry, to make sure that PCR; SEQ (SEQ has a space prepended) is recognized for the Screenings/Technique field, but the value is stored as-is, with the space. Only when the entry is edited, the space is removed. If the space is ignored when validating the field, it should be stored without the space as well.