Add skeleton for documentation (#1589)

Summary:
Pull Request resolved: https://github.com/facebook/yoga/pull/1589

Adds a skeleton to the new website of documentation and such for us to fill out.

Reviewed By: joevilches

Differential Revision: D54567186

fbshipit-source-id: 700dfe0787fcb9806c3daa0675e838540119bbc0

website-next/docs/examples/align-content.mdx

@@ -0,0 +1,15 @@
+---
+sidebar_position: 1
+---
+
+import Playground from '@site/src/components/Playground';
+
+# Align Content
+
+<Playground code={`<Layout config={{useWebDefaults: false}}>
+  <Node
+    style={{width: 200, height: 200, padding: 20}}
+  >
+    <Node style={{flex: 1}} />
+  </Node>
+</Layout>`} />