Create camera, layers and projection if not specified

skeleton.html

@@ -7,23 +7,14 @@
                 <script src="http://localhost:9810/compile?id=ol&mode=RAW" type="text/javascript"></script>
 		<script>
 
-			var projection = ol.Projection.createFromCode('EPSG:3857');
+			var target = document.getElementById('map');
+			var map = new ol.Map(target);
 
 			var layer = ol.TileLayer.createOpenStreetMap({
 				'opacity': 0.5,
 				'visible': true
 			});
-
-			var layers = new ol.Array([layer]);
-
-			var camera = new ol.Camera();
-
-			var target = document.getElementById('map');
-			var map = new ol.Map(target, {
-				'camera': camera,
-				'layers': layers,
-				'projection': projection
-			});
+			map.getLayers().push(layer);
 
 		</script>
 	</body>