use Röntgen icon for more presets and field-values

presets:
* Diving Platform
* City Limit Sign
* Turning Loop

fields values:
* `design` field of Power Poles and Power Towers/Portals
* `leaf_type`
* `traffic_calming`
* `volcano:type` and `volcano:status`
* `tower:construction`

data/presets/power/pole.json

@@ -3,6 +3,7 @@
     "fields": [
         "ref",
         "operator",
+        "design_power_pole",
         "height",
         "material",
         "line_attachment"

data/presets/power/portal.json

@@ -8,7 +8,7 @@
     ],
     "moreFields": [
         "colour",
-        "design",
+        "design_power_tower",
         "height",
         "line_management",
         "manufacturer"

data/presets/power/tower.json

@@ -3,11 +3,11 @@
     "fields": [
         "ref",
         "operator",
-        "design",
+        "structure_power",
+        "design_power_tower",
         "height",
         "material",
-        "line_attachment",
-        "structure_power"
+        "line_attachment"
     ],
     "moreFields": [
         "line_management",
@@ -18,7 +18,8 @@
         "vertex"
     ],
     "terms": [
-        "power"
+        "power",
+        "power tower"
     ],
     "tags": {
         "power": "tower"