Add custom edit url for ui-components page

Summary:
This page is auto generated, so the default link gives a 404.
Pointing it to the script instead.

Reviewed By: passy

Differential Revision: D21325554

fbshipit-source-id: 5ede07daa6335ad0199a11c5483e328c3ca2c5e3

website/generate-uidocs.js

@@ -16,6 +16,7 @@ const docblockParser = require('docblock-parser');
 const HEADER = `---
 id: ui-components
 title: UI Components
+custom_edit_url: 'https://github.com/facebook/flipper/blob/master/website/generate-uidocs.js'
 ---
 
 Flipper has a lot of built in React components to build UIs. You can import them directly using e.g. \`import {Button} from 'flipper'\`.`;