Add "Hard Rock CoffeeScript" (#6543)

* Add "Hard Rock CoffeeScript"

Added "Hard Rock CoffeeScript" and link

* Update books/free-programming-books-langs.md
Co-authored-by: NDavid Ordás <3125580+davorpa@users.noreply.github.com>

* Update books/free-programming-books-langs.md
Co-authored-by: NDavid Ordás <3125580+davorpa@users.noreply.github.com>

* Update books/free-programming-books-langs.md
Co-authored-by: NDavid Ordás <3125580+davorpa@users.noreply.github.com>
Co-authored-by: NDavid Ordás <3125580+davorpa@users.noreply.github.com>

books/free-programming-books-langs.md

@@ -568,8 +568,9 @@ That section got so big, we decided to split it into its own file, the [BY SUBJE
 
 * [CoffeeScript Cookbook](https://coffeescript-cookbook.github.io)
 * [CoffeeScript Ristretto](https://leanpub.com/coffeescript-ristretto/read) - Reginald Braithwaite  *(Leanpub account or valid email requested)*
+* [Hard Rock CoffeeScript](https://alchaplinsky.github.io/hard-rock-coffeescript/) - Alex Chaplinsky (gitbook)
 * [Smooth CoffeeScript](http://autotelicum.github.io/Smooth-CoffeeScript/SmoothCoffeeScript.html)
-* [The Little Book on CoffeeScript](http://arcturo.github.io/library/coffeescript/)
+* [The Little Book on CoffeeScript](http://arcturo.github.io/library/coffeescript/) - Alex MacCaw, David Griffiths, Satoshi Murakami, Jeremy Ashkenas
 
 
 ### ColdFusion