* simworld.cc: avoid another division by zero
* bauer/warenbauer.cc: change very ugly code to use get_text() instead of private member
* besch/text_besch.h: revert code change originally needed to make the commuters hack work.
* simworld.cc: move add_passengers_succeeded_(non_)local to happen on arrival
* simcity.cc, simcity.h: add code to downgrade rather than "renovate" a city building
* simcity.cc: effectively disable building of com/ind buildings for now.