Added "Scala Cookbook: Bonus Chapters"

free-programming-books.md

@@ -1327,6 +1327,7 @@ See also [TeX](#tex)
 * [Programming in Scala, First Edition](http://www.artima.com/pins1ed/)
 * [Programming Scala](http://programming-scala.labs.oreilly.com/index.html)
 * [Scala By Example](http://www.scala-lang.org/docu/files/ScalaByExample.pdf) (PDF)
+* [Scala Cookbook: Bonus Chapters](http://examples.oreilly.com/9781449339616-files/Scala_Cookbook_bonus_chapters.pdf) - Alvin Alexander
 * [Scala & Design Patterns: Exploring Language Expressivity](http://www.scala-lang.org/old/sites/default/files/FrederikThesis.pdf) - Fredrik Skeel Løkke
 * [Scala for the Impatient (A1 Scala Level chapters)](http://typesafe.com/resources/book/scala-for-the-impatient) - Cay S. Horstmann
 * [Scala School by Twitter](http://twitter.github.io/scala_school/)