JSX style

Wrote some notes on the standard JSX / XHP style

CONTRIBUTING.md

@@ -67,6 +67,14 @@ Facebook has a [bounty program](https://www.facebook.com/whitehat/) for the safe
 * Do not use the optional parameters of `setTimeout` and `setInterval`
 * 80 character line length
 
+#### JSX
+
+* Prefer `'` over `"` for string literal props
+* When wrapping opening tags over multiple lines, place one prop per line
+* `{}` of props should hug their values (no spaces)
+* Place the closing `>` of opening tags on the same line as the last prop
+* Place the closing `/>` of self-closing tags on their own line and left-align them wih the opening `<`
+
 #### Objective-C
 
 * Space after `@property` declarations