Tests/LibWeb: Restructure Ref and Screenshot test dirs to match others

Now each test type has the same directories:
- input
- expected
- data

Also, tests can be in subdirectories within ./input.

Tests/LibWeb/Screenshot/input/canvas-path-rect.html

@@ -0,0 +1,40 @@
+<link rel="match" href="../expected/canvas-path-rect-ref.html" />
+<style>
+  * {
+    margin: 0;
+  }
+  body {
+    background-color: white;
+  }
+</style>
+<canvas width=500 height=500></canvas>
+<script>
+    function drawRect() {
+        var canvas = document.querySelector("canvas");
+        var ctx = canvas.getContext("2d");
+        ctx.fillStyle = 'black';
+        ctx.fillRect(0, 0, 500, 500);
+
+        ctx.fillStyle = 'red';
+        ctx.beginPath();
+        ctx.rect(10, 20, 150, 100);
+        ctx.fill();
+
+        ctx.fillStyle = 'yellow';
+        ctx.beginPath();
+        ctx.roundRect(50, 310, 100, 100, 25);
+        ctx.fill('evenodd');
+
+        ctx.fillStyle = 'green';
+        ctx.beginPath();
+        ctx.rect(200, 210, 100, 100);
+        ctx.fill('evenodd');
+
+        ctx.rotate(0.2);
+        ctx.fillStyle = 'orange';
+        ctx.beginPath();
+        ctx.roundRect(325, 300, 100, 100, [ { x: 5, y: 20 }, 10, { x: 15, y: 30 }, 20 ]);
+        ctx.fill('evenodd');
+    }
+    drawRect();
+</script>