Use standardized values for establishmentMeans

[peterdesmet]

GBIF now has a filter on establishmentMeans in the occurrence search:

The filter accepts the 6 values defined in http://rs.gbif.org/vocabulary/gbif/establishment_means.xml.

Since we've stuffed some more info in that field for the bullfrog dataset (invasive alien A1), those records cannot be found. I would stick to the 6 values and add extra information (A1) in dynamicProperties or taxonRemarks.

• @DimEvil, we need to verify this in Alien macroinvertebrates as well
• @stijnvanhoey, we need to check this in Chinese mitten crab as well