Yoga Docs: Rename website-next to website (#1613)

Summary:
Pull Request resolved: https://github.com/facebook/yoga/pull/1613

So that GitHub links to edit a page point to the right place.

This will fail in OSS build until I switch the directory used by Vercel instance, but I am waiting to do that until ready to land, since that would cause other in progress changes to fail when exported.

Reviewed By: joevilches

Differential Revision: D54837857

fbshipit-source-id: 9bec90232dbe3ec8638568685671185d597fcf2d

website/docs/styling/align-content.mdx

@@ -0,0 +1,47 @@
+---
+sidebar_position: 1
+---
+
+import Playground from '@site/src/components/Playground';
+
+# Align Content
+
+Align content defines the distribution of lines along the cross-axis. This only
+has effect when items are wrapped to multiple lines using [flex wrap](/docs/styling/flex-wrap).
+
+**Flex start (default)**: Align wrapped lines to the start of the container's cross axis.
+
+**Flex end**: Align wrapped lines to the end of the container's cross axis.
+
+**Stretch**: Stretch wrapped lines to match the [height](/docs/styling/width-height) of the container's cross axis.
+
+**Center**: Align wrapped lines in the center of the container's cross axis.
+
+**Space between**: Evenly space wrapped lines across the container's main axis, distributing
+remaining space between the lines.
+
+**Space around**: Evenly space wrapped lines across the container's main axis, distributing
+remaining space around the lines. Compared to space between using
+space around will result in space being distributed to the begining of
+the first lines and end of the last line.
+
+**Space evenly**: Evenly space wrapped lines across the container's main axis, distributing
+remaining space around the lines. Compared to space around, space evenly will not
+double the gaps between children. The size of gaps between children and between
+the parent's edges and the first/last child will all be equal.
+
+<Playground code={`<Layout config={{useWebDefaults: false}}>
+  <Node
+    style={{
+      width: 200,
+      height: 250,
+      padding: 10,
+      alignContent: 'flex-start',
+      flexWrap: 'wrap',
+    }}>
+    <Node style={{margin: 5, height: 50, width: 50}} />
+    <Node style={{margin: 5, height: 50, width: 50}} />
+    <Node style={{margin: 5, height: 50, width: 50}} />
+    <Node style={{margin: 5, height: 50, width: 50}} />
+  </Node>
+</Layout>`} />