Clean up certain style choices on website's example documentation (#1616)

Summary:
Pull Request resolved: https://github.com/facebook/yoga/pull/1616

This is based on a few comments earlier in the stack and my own discretion on what should change. But I went through all of the examples and changed the following:

* Only add code tick marks in a few cases where it would make sense. Things like `start` and `end`, `undefined` as a value, etc. There ends up not being that many after this. Previously, any property or value was tick marked even if it was more of a concept than actual code. **I replaced those cases with a link to their respective documentation as I feel like this keeps the indication that this is a keyword without labeling it as code**.
* Any reference to "element" was changed to "node"
* Capitalize words that follow a colon
* Run code examples through prettier for consistent style

Reviewed By: yungsters

Differential Revision: D54816609

fbshipit-source-id: 20ee925cf46bd1c519cc88bab9327321e926ac56

website-next/docs/styling/display.mdx

@@ -19,7 +19,7 @@ Display controls which layout specification to follow.
       height: 200,
       padding: 10,
     }}>
-    <Node style={{margin: 5, height: 50, display: 'flex'}} />
     <Node style={{margin: 5, height: 50, display: 'none'}} />
+    <Node style={{margin: 5, height: 50, display: 'flex'}} />
   </Node>
 </Layout>`} />