Add Site Reliability Engineering (#2793)

free-programming-books.md

@@ -705,6 +705,7 @@ Kerridge (PDF) (Just fill the fields with any values)
 * [Reactive Microservices Architecture](http://www.oreilly.com/programming/free/reactive-microservices-architecture-orm.csp) *(Just fill the fields with any values)*
 * [Scrum and XP from the Trenches](http://www.infoq.com/minibooks/scrum-xp-from-the-trenches-2)
 * [Seamless Object-Oriented Software Architecture](http://www.bon-method.com/book_print_a4.pdf) (PDF)
+* [Site Reliability Engineering](https://landing.google.com/sre/book/index.html)
 * [Software Architecture Patterns](http://www.oreilly.com/programming/free/software-architecture-patterns.csp) *(Just fill the fields with any values)*
 * [Software Engineering for Internet Applications](http://philip.greenspun.com/seia/)
 * [Test Driven Development, Extensive Tutorial](https://github.com/grzesiek-galezowski/tdd-ebook) - Daniel Żołopa