Update getting started guide to reference new book version (#311)

Author: drewolson

guides/Getting-Started.md

@@ -237,7 +237,7 @@ The `spago run` command can be used to compile and run the `Main` module:
 
 #### What Next?
 
-If you're new to typed functional programming, your next stop should be [PureScript by Example](https://leanpub.com/purescript/read), which will walk you through learning PureScript by solving practical problems. (Note: At the time of writing, _Purescript by Example_ is compatible with the 0.11.x version of the compiler)
+If you're new to typed functional programming, your next stop should be [PureScript by Example](https://book.purescript.org/), which will walk you through learning PureScript by solving practical problems.
 
 If you are already familiar with an ML-family language, like Haskell or Elm, PureScript by Example should still be appropriate as a starting point, but you may alternatively want to start by browsing the [language reference in the documentation repository](https://github.com/purescript/documentation/tree/master/language) instead. The language reference gives a more brief, reference-style description of the language, and is aimed at those who are already somewhat familiar with typed functional programming. There is also a [Differences from Haskell](https://github.com/purescript/documentation/blob/master/language/Differences-from-Haskell.md) page which Haskell programmers will find useful.