add fields for diameter & height of wind turbines, closes #241

and also match features without `generator:method=wind_turbine` set, and suggest to add it

data/fields/height/hub.json

@@ -0,0 +1,6 @@
+{
+    "key": "height:hub",
+    "minValue": 0,
+    "type": "number",
+    "label": "Height of Hub (Meters)"
+}

data/fields/rotor/diameter.json

@@ -0,0 +1,6 @@
+{
+    "key": "rotor:diameter",
+    "minValue": 0,
+    "type": "number",
+    "label": "Rotor Diameter (Meters)"
+}

data/presets/power/generator/source/wind.json

@@ -7,7 +7,9 @@
         "generator/output/electricity"
     ],
     "moreFields": [
-        "{power/generator}"
+        "{power/generator}",
+        "height/hub",
+        "rotor/diameter"
     ],
     "geometry": [
         "point",
@@ -15,6 +17,10 @@
         "area"
     ],
     "tags": {
+        "power": "generator",
+        "generator:source": "wind"
+    },
+    "addTags": {
         "power": "generator",
         "generator:source": "wind",
         "generator:method": "wind_turbine"