Add setting to increase station catchment radius.

Update acceptance and refresh screen when catchment settings change.

src/table/settings.ini

@@ -1358,6 +1358,20 @@ strhelp  = STR_CONFIG_SETTING_CATCHMENT_HELPTEXT
 proc     = StationCatchmentChanged
 cat      = SC_EXPERT
 
+[SDT_VAR]
+base     = GameSettings
+var      = station.catchment_increase
+type     = SLE_UINT8
+def      = 0
+min      = 0
+max      = 5
+str      = STR_CONFIG_SETTING_CATCHMENT_INCREASE
+strhelp  = STR_CONFIG_SETTING_CATCHMENT_INCREASE_HELPTEXT
+strval   = STR_JUST_COMMA
+proc     = StationCatchmentChanged
+extver   = SlXvFeatureTest(XSLFTO_AND, XSLFI_STATION_CATCHMENT_INC)
+patxname = ""station_catchment_inc.station.catchment_increase""
+
 [SDT_BOOL]
 base     = GameSettings
 var      = order.gradual_loading