add matched keywords to public.records table per category

[pvgenuchten]

in #20 we categorised keywords by filter theme
for each filter theme we should add a column to public.records (see #26) with the relevant matched keywords per theme

identifier	soilthreat	soilfunction	soilproperty
111-222-333	erosion	fertility	calcium, potassium
aaa-bbb-ccc	polution	human health	cadmium
10.100/aaa		Air quality, Human health	soil organic carbon