FIX possible read in undefined memory - gr is invalid here already

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@6887 8aca7d54-2c30-db11-9de9-000461428c89
(Max-Max) More debug message to images (and prissi made consequent use of debug system

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@6888 8aca7d54-2c30-db11-9de9-000461428c89
(Max-Max) More debug message to images (and prissi made consequent use of debug system) right folder this time to commit ...

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@6889 8aca7d54-2c30-db11-9de9-000461428c89
Merge remote-tracking branch 'upstream/master'