Storybook docs structure (#3755)

* updated naming of common to documentation

* Add button docs

* updated sort order

Documentation is now above the component library and allows the general pages to come before the component specific ones.

* fixed typos

* updated file name

* fixed typo in introduction.stories.mdx

* updated banner.stories.mdx to match new docs structure

* remove plural in button docs

.storybook/preview.js

@@ -12,6 +12,11 @@ export const parameters = {
       date: /Date$/,
     },
   },
+  options: {
+    storySort: {
+      order: ["Documentation", ["Introduction", "Colors", "Icons"], "Component Library"],
+    },
+  },
   docs: { inlineStories: true },
 };