Added Redbubble logo (graphql#113)

* Added Redbubble logo.

* Fixed quote

Author: tomjadams

site/users/index.html.js

@@ -114,6 +114,11 @@ var logos = [
     name: 'OK GROW!',
     img: 'okgrow.png',
     link: 'https://www.okgrow.com/graphql'
+  },
+  {
+    name: 'Redbubble',
+    img: 'redbubble.png',
+    link: 'https://www.redbubble.com/'
   }
   // Adding your logo?
   // Add it to the /users/logos/ directory and then append an entry above this comment.