Added information about an artspace.

Hochschule Düsseldorf has moved since many years, please delete Mensa and Hochschulbibliothek.

This part of the L 12 is still usable. If marked as a service road, it won't appear on the map as accessible. Note that given the juridical situation, it may or may not be closed in the near future.

The Freinet School has moved some years ago. I've corrected the names of the schools.