FIX: when making halts public make sure that no connections are dropped and freight gets lost

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@7349 8aca7d54-2c30-db11-9de9-000461428c89
CODE: reset env_t::restore_UI, remove unused variable

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@7350 8aca7d54-2c30-db11-9de9-000461428c89
CODE: factor out speed-bonus calculation into ware_t::calc_revenue

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@7351 8aca7d54-2c30-db11-9de9-000461428c89
FIX and update sqapi doc

git-svn-id: svn://tron.homeunix.org/simutrans/simutrans/trunk@7352 8aca7d54-2c30-db11-9de9-000461428c89