Adjust end date slightly to avoid rendering the old and new road at the same time

Remove start_date from farmland where the start date isn't actually known

Set better end_date values to help with rendering

Map some landuse changes and related highway/road construction

Lillestrøm: move start_date ranges to start_date:edtf

Move start_date ranges to :edtf, add more roads, and add WW2 runway

Add Kongsvingerbanen and extend Hovedbanen to the edge of the Lillestrøm 1939 map

Connect Hovedbanen and Lillestrøm station to Wikidata, and add correct start_date

Add exact start_date for schools in Lillestrøm and adjust high school names slightly

Roughly map expansion of Lillestrøm 1939-1986