crash start rework

data/json/mapgen/map_extras/mayhem.json

@@ -8,6 +8,15 @@
       "place_nested": [ { "chunks": [ "24x24_mayhem_crash", "24x24_mayhem_limo", "24x24_mayhem_tire_change" ], "x": 0, "y": 0 } ]
     }
   },
+  {
+    "type": "mapgen",
+    "method": "json",
+    "update_mapgen_id": "mx_mayhem_crash_start",
+    "object": {
+      "flags": [ "ALLOW_TERRAIN_UNDER_OTHER_DATA" ],
+      "place_nested": [ { "chunks": [ "24x24_mayhem_crash" ], "x": 0, "y": 0 } ]
+    }
+  },
   {
     "type": "mapgen",
     "method": "json",
@@ -50,6 +59,7 @@
         "2": [ { "item": "corpses", "chance": 100 }, { "item": "guns_pistol_common_display", "chance": 80 } ]
       },
       "place_item": [ { "item": "9mm_casing", "x": [ 15, 17 ], "y": [ 2, 4 ], "chance": 50, "repeat": 9 } ],
+      "place_zones": [ { "type": "ZONE_START_POINT", "faction": "your_followers", "x": [ 18, 18 ], "y": [ 9, 9 ] } ],
       "fields": { "1": { "field": "fd_blood", "intensity": [ 1, 3 ] }, "~": { "field": "fd_blood" }, "2": { "field": "fd_blood" } },
       "flags": [ "ALLOW_TERRAIN_UNDER_OTHER_DATA" ]
     }

data/json/overmap/map_extras.json

@@ -59,6 +59,18 @@
     "autonote": true,
     "flags": [ "MAN_MADE", "CLASSIC" ]
   },
+  {
+    "id": "mx_mayhem_crash_start",
+    "type": "map_extra",
+    "name": { "str": "Car Crash" },
+    "description": "Car crash is here.",
+    "generator": { "generator_method": "update_mapgen", "generator_id": "mx_mayhem_crash_start" },
+    "min_max_zlevel": [ 0, 0 ],
+    "sym": "M",
+    "color": "light_red",
+    "autonote": true,
+    "flags": [ "MAN_MADE", "CLASSIC" ]
+  },
   {
     "id": "mx_roadblock",
     "type": "map_extra",

data/json/scenarios.json

@@ -941,7 +941,7 @@
     "description": "You decided the open road would be a better prospect than the zombie-filled cities.  While en route to your destination, you were involved in a crash that totaled your vehicle.  Injured and alone, you'll need to think fast if you want to survive.",
     "allowed_locs": [ "sloc_road" ],
     "start_name": "Crash Site",
-    "map_extra": "mx_mayhem",
+    "map_extra": "mx_mayhem_crash_start",
     "flags": [ "CHALLENGE", "HELI_CRASH", "LONE_START" ]
   },
   {

data/json/start_locations.json

@@ -693,6 +693,7 @@
     "type": "start_location",
     "id": "sloc_road",
     "name": "Road",
+    "city_distance": [ 10, -1 ],
     "terrain": [ { "om_terrain": "road", "om_terrain_match_type": "TYPE" } ]
   },
   {