Added the list from https://code.google.com/p/google-styleguide/, which includes C++, Objective C, Java, Python, HTML/CSS, and Common Lisp. Also added is Ian McDonald's Ruby guide, which was used internally on an unofficial basis but is also thorough.

Adding AutoHotkey Book

a free online book about AutoHotkey. AHK is free, open-source scripting
language for Windows - more at www.ahkscript.org and www.autohotkey.com

Turkish: git tutorial & Indexing

Remove duplicate entry - Heskell

The removed line corresponds with the Haskell Wikibook link which is already present. (The wikibook link is usually more updated than the removed pdf version. Also you can download pdf version of this book from the wikibook link.)

Fixed link in table of contents to .NET section

Added postgresql section.

Quick fix to zh list

move some non x86 to the non-x86 section

added several books

added more free Chinese programming books in:
* git
* ruby
* LISP
* Haskell
* Scala
* Shell script

Adding RESTful Web Services book

Update Scheme #532

Update free-programming-books-zh.md

Codecademy is a very impressive online programming language learning system.

Moved HtDP and SICP from "free-programming-books-en.md"

Fix index link in ru file

Update free-programming-books-de.md

Fix two index links in japanese file

Added missing Pro Git eBook with the german translation.

Added PHP section to spanish version (free-programming-books.md)

The c++ contextual link did not work.

This reverts commit aa26bdab.

The c++ contextual link did not work.