Update default project with new more compact serialization.

src/lib/default-project/project.json

 {
-	"targets": [
-		{
-			"id": "`jEk@4|i[#Fk?(8x)AV.",
-			"name": "Stage",
-			"isStage": true,
-			"x": 0,
-			"y": 0,
-			"size": 100,
-			"direction": 90,
-			"draggable": false,
-			"currentCostume": 0,
-			"costume": {
-				"name": "backdrop1",
-				"bitmapResolution": 1,
-				"rotationCenterX": 240,
-				"rotationCenterY": 180,
-				"skinId": 2,
-				"dataFormat": "png",
-				"assetId": "739b5e2a2435f6e1ec2993791b423146"
-			},
-			"costumeCount": 1,
-			"visible": true,
-			"rotationStyle": "all around",
-			"blocks": {},
-			"variables": {
-				"`jEk@4|i[#Fk?(8x)AV.-my variable": {
-					"id": "`jEk@4|i[#Fk?(8x)AV.-my variable",
-					"name": "my variable",
-					"type": "",
-					"isCloud": false,
-					"value": 0
-				}
-			},
-			"lists": {},
-			"costumes": [
-				{
-					"name": "backdrop1",
-					"bitmapResolution": 1,
-					"rotationCenterX": 240,
-					"rotationCenterY": 180,
-					"skinId": 2,
-					"dataFormat": "png",
-					"assetId": "739b5e2a2435f6e1ec2993791b423146"
-				}
-			],
-			"sounds": [
-				{
-					"name": "pop",
-					"format": "",
-					"rate": 11025,
-					"sampleCount": 258,
-					"soundID": 1,
-					"md5ext": "83a9787d4cb6f3b7632b4ddfebf74367.wav",
-					"data": null,
-					"dataFormat": "wav",
-					"assetId": "83a9787d4cb6f3b7632b4ddfebf74367",
-					"soundId": "p=i?*Zt*I]@]x_*V`mut"
-				}
-			]
-		},
-		{
-			"id": "9xJ@2eKXvx:/*Q^3Rib#",
-			"name": "Sprite1",
-			"isStage": false,
-			"x": 0,
-			"y": 0,
-			"size": 100,
-			"direction": 90,
-			"draggable": false,
-			"currentCostume": 0,
-			"costume": {
-				"name": "costume1",
-				"bitmapResolution": 1,
-				"rotationCenterX": 47,
-				"rotationCenterY": 55,
-				"skinId": 0,
-				"dataFormat": "svg",
-				"assetId": "09dc888b0b7df19f70d81588ae73420e"
-			},
-			"costumeCount": 2,
-			"visible": true,
-			"rotationStyle": "all around",
-			"blocks": {},
-			"variables": {},
-			"lists": {},
-			"costumes": [
-				{
-					"name": "costume1",
-					"bitmapResolution": 1,
-					"rotationCenterX": 47,
-					"rotationCenterY": 55,
-					"skinId": 0,
-					"dataFormat": "svg",
-					"assetId": "09dc888b0b7df19f70d81588ae73420e"
-				},
-				{
-					"name": "costume2",
-					"bitmapResolution": 1,
-					"rotationCenterX": 47,
-					"rotationCenterY": 55,
-					"skinId": 1,
-					"dataFormat": "svg",
-					"assetId": "3696356a03a8d938318876a593572843"
-				}
-			],
-			"sounds": [
-				{
-					"name": "Meow",
-					"format": "",
-					"rate": 22050,
-					"sampleCount": 18688,
-					"soundID": 0,
-					"md5ext": "83c36d806dc92327b9e7049a565c6bff.wav",
-					"data": null,
-					"dataFormat": "wav",
-					"assetId": "83c36d806dc92327b9e7049a565c6bff",
-					"soundId": "]z6@jLeJ2W%gr/eA1HB+"
-				}
-			]
-		}
-	],
-	"meta": {
-		"semver": "3.0.0",
-		"vm": "0.1.0",
-		"agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/64.0.3282.186 Safari/537.36"
-	}
+  "targets": [
+    {
+      "isStage": true,
+      "name": "Stage",
+      "variables": {
+        "`jEk@4|i[#Fk?(8x)AV.-my variable": [
+          "my variable",
+          0
+        ]
+      },
+      "lists": {},
+      "broadcasts": {},
+      "blocks": {},
+      "currentCostume": 0,
+      "costumes": [
+        {
+          "assetId": "739b5e2a2435f6e1ec2993791b423146",
+          "name": "backdrop1",
+          "bitmapResolution": 1,
+          "md5ext": "739b5e2a2435f6e1ec2993791b423146.png",
+          "dataFormat": "png",
+          "rotationCenterX": 240,
+          "rotationCenterY": 180
+        }
+      ],
+      "sounds": [
+        {
+          "assetId": "83a9787d4cb6f3b7632b4ddfebf74367",
+          "name": "pop",
+          "dataFormat": "wav",
+          "format": "",
+          "rate": 11025,
+          "sampleCount": 258,
+          "md5ext": "83a9787d4cb6f3b7632b4ddfebf74367.wav"
+        }
+      ],
+      "volume": 100,
+      "tempo": 60,
+      "videoTransparency": 50,
+      "videoState": "off"
+    },
+    {
+      "isStage": false,
+      "name": "Sprite1",
+      "variables": {},
+      "lists": {},
+      "broadcasts": {},
+      "blocks": {},
+      "currentCostume": 0,
+      "costumes": [
+        {
+          "assetId": "09dc888b0b7df19f70d81588ae73420e",
+          "name": "costume1",
+          "bitmapResolution": 1,
+          "md5ext": "09dc888b0b7df19f70d81588ae73420e.svg",
+          "dataFormat": "svg",
+          "rotationCenterX": 47,
+          "rotationCenterY": 55
+        },
+        {
+          "assetId": "3696356a03a8d938318876a593572843",
+          "name": "costume2",
+          "bitmapResolution": 1,
+          "md5ext": "3696356a03a8d938318876a593572843.svg",
+          "dataFormat": "svg",
+          "rotationCenterX": 47,
+          "rotationCenterY": 55
+        }
+      ],
+      "sounds": [
+        {
+          "assetId": "83c36d806dc92327b9e7049a565c6bff",
+          "name": "Meow",
+          "dataFormat": "wav",
+          "format": "",
+          "rate": 22050,
+          "sampleCount": 18688,
+          "md5ext": "83c36d806dc92327b9e7049a565c6bff.wav"
+        }
+      ],
+      "volume": 100,
+      "visible": true,
+      "x": 0,
+      "y": 0,
+      "size": 100,
+      "direction": 90,
+      "draggable": false,
+      "rotationStyle": "all around"
+    }
+  ],
+  "meta": {
+    "semver": "3.0.0",
+    "vm": "0.1.0",
+    "agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36"
+  }
 }