Convert to Swift 4.0 syntax

XIONControlPanel/SupportingFiles/Assets.xcassets/AppIcon.appiconset/Contents.json

@@ -1,5 +1,15 @@
 {
   "images" : [
+    {
+      "idiom" : "iphone",
+      "size" : "20x20",
+      "scale" : "2x"
+    },
+    {
+      "idiom" : "iphone",
+      "size" : "20x20",
+      "scale" : "3x"
+    },
     {
       "size" : "29x29",
       "idiom" : "iphone",
@@ -36,6 +46,16 @@
       "filename" : "Icon-60@3x.png",
       "scale" : "3x"
     },
+    {
+      "idiom" : "ipad",
+      "size" : "20x20",
+      "scale" : "1x"
+    },
+    {
+      "idiom" : "ipad",
+      "size" : "20x20",
+      "scale" : "2x"
+    },
     {
       "size" : "29x29",
       "idiom" : "ipad",
@@ -77,6 +97,11 @@
       "idiom" : "ipad",
       "filename" : "Icon-167@2x.png",
       "scale" : "2x"
+    },
+    {
+      "idiom" : "ios-marketing",
+      "size" : "1024x1024",
+      "scale" : "1x"
     }
   ],
   "info" : {