added serialization of topography filter in url
added serialization of topography filter in url

cedricbonhomme/shelter-database,rodekruis/shelter-database,toggle-corp/shelter-database,toggle-corp/shelter-database,cedricbonhomme/shelter-database,toggle-corp/shelter-database,cedricbonhomme/shelter-database,rodekruis/shelter-database,rodekruis/shelter-database,toggle-corp/shelter-database,rodekruis/shelter-database,cedricbonhomme/shelter-database