basecamps: preserve rotation data for future upgrades

Now that basecamps can be built in places that aren't fields, the
basecamp overmap terrain id needs to include rotational data so that
update_mapgen will correctly place upgrades on fire stations and evac
shelters that are rotated.

data/json/mapgen/faction_buildings.json

@@ -1,7 +1,7 @@
 [
   {
     "type": "mapgen",
-    "om_terrain": [ "faction_base_camp_0" ],
+    "om_terrain": [ "faction_base_camp_0", "faction_base_camp_new_0" ],
     "method": "json",
     "weight": 250,
     "object": {

data/json/overmap/overmap_terrain/overmap_terrain_faction_base.json

@@ -8,6 +8,15 @@
     "see_cost": 5,
     "flags": [ "NO_ROTATE", "SOURCE_PEOPLE" ]
   },
+  {
+    "type": "overmap_terrain",
+    "id": "faction_base_camp_new_0",
+    "name": "survivor camp",
+    "sym": "+",
+    "color": "white",
+    "see_cost": 5,
+    "flags": [ "SOURCE_PEOPLE" ]
+  },
   {
     "type": "overmap_terrain",
     "id": "faction_base_camp_1",

src/basecamp.cpp

@@ -18,6 +18,7 @@
 #include "item_group.h"
 #include "map.h"
 #include "map_iterator.h"
+#include "overmap.h"
 #include "overmapbuffer.h"
 #include "player.h"
 #include "npc.h"
@@ -189,7 +190,8 @@ void basecamp::define_camp( const tripoint &p, const std::string &camp_type )
         e.cur_level = -1;
         e.pos = omt_pos;
         expansions[base_camps::base_dir] = e;
-        overmap_buffer.ter_set( omt_pos, oter_id( "faction_base_camp_0" ) );
+        overmap_buffer.ter_set( omt_pos, oter_id( "faction_base_camp_new_0" +
+                                oter_get_rotation_string( omt_ref ) ) );
         update_provides( base_camps::faction_encode_abs( e, 0 ),
                          expansions[base_camps::base_dir] );
     } else {