Add roller coaster presets (#985)

Adds presets for:

* roller_coaster=track
* roller_coaster=station
* roller_coaster=support

Also adds a field for roller_coaster:track=* and the layer field to attraction=water_slide

data/fields/roller_coaster/track.json

@@ -0,0 +1,37 @@
+{
+    "key": "roller_coaster",
+    "type": "combo",
+    "label": "Type",
+    "strings": {
+        "options": {
+            "lift_hill": {
+                "title": "Lift Hill",
+                "description": "An inclined track meant to give the trains potential energy"
+            },
+            "launch_straight": {
+                "title": "Launch Track",
+                "description": "A section of track meant to accelerate the trains through external input"
+            },
+            "brake_run": {
+                "title": "Brake Run",
+                "description": "A section of track meant to slow or stop trains"
+            },
+            "station": {
+                "title": "Station",
+                "description": "A section of track where a train stops to board and unboard passengers"
+            },
+            "moving": {
+                "title": "Moving",
+                "description": "Any type of moving track, like switch tracks"
+            },
+            "waiting": {
+                "title": "Waiting",
+                "description": "Tracks used to hold trains if the next block section is occupied"
+            },
+            "maintenance": {
+                "title": "Maintenance",
+                "description": "Tracks meant to hold spare trains or conduct maintenance"
+            }
+        }
+    }
+}