FIX: correctly (un)set zoomable flag on tool icons

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@7162 8aca7d54-2c30-db11-9de9-000461428c89
FIX: hang up in background by creating and processing our own WM_TIMER events ...

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@7163 8aca7d54-2c30-db11-9de9-000461428c89
Keep runways longer reserved

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@7164 8aca7d54-2c30-db11-9de9-000461428c89