CHG: when upgrading stations compare capacity
FIX: cost calculation when upgrading stations


git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@7092 8aca7d54-2c30-db11-9de9-000461428c89
FIX: offset of factory highlighting box in minimap when map is rotated

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@7093 8aca7d54-2c30-db11-9de9-000461428c89
CODE: const correctness, init variable

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@7094 8aca7d54-2c30-db11-9de9-000461428c89