add preset for man_made=video_wall (#230)

Author: k-yle

data/fields/min_height.json

@@ -0,0 +1,9 @@
+{
+    "key": "min_height",
+    "minValue": 0,
+    "type": "number",
+    "label": "Height of bottom (Meters)",
+    "prerequisiteTag": {
+        "key": "height"
+    }
+}

data/presets/man_made/video_wall.json

@@ -0,0 +1,32 @@
+{
+    "icon": "temaki-billboard",
+    "fields": [
+        "support",
+        "operator",
+        "height",
+        "min_height"
+    ],
+    "moreFields": [
+        "name",
+        "ref",
+        "website",
+        "visibility"
+    ],
+    "geometry": [
+        "point",
+        "vertex",
+        "line"
+    ],
+    "terms": [
+        "screen",
+        "tv",
+        "television",
+        "display",
+        "video wall",
+        "led wall"
+    ],
+    "tags": {
+        "man_made": "video_wall"
+    },
+    "name": "Digital Screen"
+}