* dataobj/replace_data.cc: fix potential stack overflow that AddressSanitizer caught
* gui/convoi_info_t.cc: fix compiler warning
* gui/replace_frame.cc: fix potential stack overflows caught by AddressSanitizer
* simcity.cc: don't build on cliffs, except on those that have three raised corners.
* simware.cc: remove debug messages
* simcity.cc, simworld.cc: avoid some crashes that I only saw during loading, and that probably shouldn't happen anyway
* Makefile: build with gcc-4.8, so AdressSanitizer works
* simcity.cc: treat industry like other buildings in build_city_building
experiment: keep a single growth score per building, which results in downgrades/upgrades when it exceeds the population.
* simcity.cc: fix downgrade_city_building
* simcity.cc: add a warning message to the bridge building code for the remaining cases when we build a bridge to a blocked tile
* simcity.cc: whitespace