sqapi: scenario can check whether player can use certain schedules

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@6345 8aca7d54-2c30-db11-9de9-000461428c89
CHG: when loading savegame with scenario try to load script from addon directory first, then from pakset directory

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@6346 8aca7d54-2c30-db11-9de9-000461428c89
FIX: load scenario script from pakset again

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@6347 8aca7d54-2c30-db11-9de9-000461428c89
sqapi: add halt_x::is_connected

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@6348 8aca7d54-2c30-db11-9de9-000461428c89