Update power presets following transformer tagging extension (#447)

data/fields/windings/auto.json

@@ -0,0 +1,12 @@
+{
+    "key": "windings:auto",
+    "type": "check",
+    "label": "Autotransformer",
+    "strings": {
+        "options": {
+            "undefined": "Assumed to be No",
+            "yes": "Yes",
+            "no": "No"
+        }
+    }
+}