Fetches and caches pollendata from https://pollenvarsel.naaf.no/charts/forecast.
- /regions - lists available regions
- /pollen/{region} - pollen data for {region}
- /forecast/{region} - text forecast for {region}
- /combined/{region} - combined pollen data and text forecast for {region}
The levels describe the amount of pollen grains per m3 of air.
- 0 - No spread (0)
- 1 - Low spread (1 - 9)
- 2 - Moderate spread (10 - 99)
- 3 - Heavy spread (100 - 999)
- 4 - Extreme spread (1000+)