No more piling up on diagonals (but so simple fix there might be a reason it was not checked before)

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@6700 8aca7d54-2c30-db11-9de9-000461428c89
No more piling up on diagonals but only of there is no crossing

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@6701 8aca7d54-2c30-db11-9de9-000461428c89