✨ Added tutorial pattern

packages/tutorial/src/step4.js

@@ -0,0 +1,34 @@
+export default function(part) {
+  let { Point, points, Path, paths, measurements, options } = part.shorthand();
+
+  points.rightCp2 = points.rightCp1.flipY();
+  points.bottomCp1 = points.bottomCp2.flipX();
+
+  points.left = points.right.flipX();
+  points.leftCp1 = points.rightCp2.flipX();
+  points.leftCp2 = points.rightCp1.flipX();
+
+  points.top = points.bottom.flipY();
+  points.topCp1 = points.bottomCp2.flipY();
+  points.topCp2 = points.bottomCp1.flipY();
+
+  paths.neck = new Path()
+    .move(points.top)
+    .curve(points.topCp2, points.leftCp1, points.left)
+    .curve(points.leftCp2, points.bottomCp1, points.bottom)
+    .curve(points.bottomCp2, points.rightCp1, points.right)
+    .curve(points.rightCp2, points.topCp1, points.top)
+    .close();
+
+  // Complete?
+  if (complete) {
+    if (sa) {
+    }
+
+    // Paperless?
+    if (paperless) {
+    }
+  }
+
+  return part;
+}