Adding psalm.bible to the list of sites built with Gatsby (#866)

Just generated a site with the entire book of Psalms in the New International Version of the Bible. It includes pages for every chapter and every verse in Psalms. Thanks for making this possible!

README.md

@@ -125,6 +125,7 @@ https://gatsbygram.gatsbyjs.org and the case study on how its built https://www.
 * [SameMoment Blog](http://blog.samemoment.com/)
 * [Kombi Labs](http://kombi.io/)
 * [harshiniraji.in](http://harshiniraji.in)
+* [Psalm.Bible](http://psalm.bible/psalm-139-16/)
 * [Edit this file to add yours!](https://github.com/gatsbyjs/gatsby/blob/master/README.md)
 
 *Note, for the sites that have made their source available, you can