remove doubled code

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@6632 8aca7d54-2c30-db11-9de9-000461428c89
greater range of heights when loading heightmaps with double heights

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@6633 8aca7d54-2c30-db11-9de9-000461428c89
move network-related code to network/

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@6634 8aca7d54-2c30-db11-9de9-000461428c89