Merge branch 'everest_treeline-sx' into jgrpp

src/settings_type.h

@@ -342,6 +342,8 @@ struct ConstructionSettings {
 	uint8  industry_platform;                ///< the amount of flat land around an industry
 	bool   freeform_edges;                   ///< allow terraforming the tiles at the map edges
 	uint8  extra_tree_placement;             ///< (dis)allow building extra trees in-game
+	uint8  trees_around_snow_line_range;     ///< range around snowline for mixed and arctic forest.
+	bool   trees_around_snow_line_enabled;   ///< enable mixed and arctic forest around snowline, and no trees above snowline
 	uint8  command_pause_level;              ///< level/amount of commands that can't be executed while paused
 	uint16 maximum_signal_evaluations;       ///< maximum number of programmable signals which may be evaluated in one pass
 	byte   simulated_wormhole_signals;       ///< simulate signals in tunnel