adding layout support

cybersyn/scripts/constants.lua

@@ -18,3 +18,15 @@ STATUS_P = 2
 STATUS_P_TO_R = 3
 STATUS_R = 4
 STATUS_R_TO_D = 5
+
+TRAIN_LAYOUT_NA = "N"
+TRAIN_LAYOUT_CARGO = "C"
+TRAIN_LAYOUT_FLUID = "F"
+--TRAIN_LAYOUT_ARTILLERY = "A"
+
+STATION_LAYOUT_NA = "N"
+STATION_LAYOUT_CARGO = "C"
+STATION_LAYOUT_FLUID = "F"
+STATION_LAYOUT_BOTH = "."
+
+LONGEST_INSERTER_REACH = 2