Merge branch 'town_cargo_adj-sx' into jgrpp

Conflicts:
	src/saveload/extended_ver_sl.cpp
	src/saveload/extended_ver_sl.h

src/settings_type.h

@@ -510,6 +510,7 @@ struct EconomySettings {
 	bool   station_noise_level;              ///< build new airports when the town noise level is still within accepted limits
 	uint16 town_noise_population[3];         ///< population to base decision on noise evaluation (@see town_council_tolerance)
 	bool   allow_town_level_crossings;       ///< towns are allowed to build level crossings
+	int8   town_cargo_factor;                ///< power-of-two multiplier for town (passenger, mail) generation. May be negative.
 	bool   infrastructure_maintenance;       ///< enable monthly maintenance fee for owner infrastructure
 };