Add project file

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@6796 8aca7d54-2c30-db11-9de9-000461428c89
No crash with unknow tunnel during loading

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@6797 8aca7d54-2c30-db11-9de9-000461428c89