fields/parking: centerline parking and orientation

…for case :left, :right, :both. The directionalCombo will show left/right in separate fields when both is present and merge/split the side as needed.

Allow tagging `parking:$side` and `parking:$side:orientation` on centerlines (highways).

data/fields/parking/side/orientation.json

@@ -0,0 +1,25 @@
+{
+    "keys": [
+        "parking:both:orientation",
+        "parking:left:orientation",
+        "parking:right:orientation"
+    ],
+    "reference": {
+        "key": "parking:orientation"
+    },
+    "type": "directionalCombo",
+    "label": "Parking orientation",
+    "strings": {
+        "types": {
+            "parking:left:orientation": "Left side",
+            "parking:right:orientation": "Right side"
+        },
+        "options": {
+            "parallel": "Parallel to the Street",
+            "diagonal": "Diagonal in Relation to the Street (~45°)",
+            "perpendicular": "Meets the Street at a Straight Angle (~90°)"
+        }
+    },
+    "autoSuggestions": false,
+    "customValues": false
+}

data/fields/parking/side/parking.json

@@ -0,0 +1,30 @@
+{
+    "keys": [
+        "parking:both",
+        "parking:left",
+        "parking:right"
+    ],
+    "reference": {
+        "key": "parking"
+    },
+    "type": "directionalCombo",
+    "label": "Parking",
+    "strings": {
+        "types": {
+            "parking:left": "Left side",
+            "parking:right": "Right side"
+        },
+        "options": {
+            "lane": "Roadside Lane",
+            "street_side": "Street-Side",
+            "on_kerb": "On Kerb",
+            "half_on_kerb": "Half On Kerb",
+            "shoulder": "Shoulder",
+            "no": "No",
+            "separate": "Parking mapped separately",
+            "yes": "Yes (unspecified)"
+        }
+    },
+    "autoSuggestions": false,
+    "customValues": false
+}