* Angular Course added closes #1690

* Inroduction to Rx closes #1817

* Overwork on free-prpgramming-books-zh.md

* Done #1948

* Deleted not-freely obtainable ebook closes #1930

* Added new documentation for Django. 
* Removed http://gettingstartedwithdjango.com as the site is down for a long time.
* Updated the Tango with Django book
* Removed the "The Django Book" as it was very old version of Django

* Added Happy Learn Haskell Tutorial
* corrected travis messages
* corrected Alphabetical ordering
* Remove trailing slash

the link http://google-styleguide.googlecode.com/svn/trunk/javaguide.html is broken .

The book is available for first three chapters, and email registration is required to get it.

Thank you to @eschellman for the link to the archive source.

Updated the link for http://www.mmds.org/.
Removed An Introduction to Statistics with Python as it was not free. 
Removed The Architecture of Open Source Applications as it was a duplicate. 
Removed How to Write Parallel Programs as the domain is currently for sale. 
Removed CryptoParty handbook as it doesn't exist. 
Removed Network Science book as it 404s.

1200-page ebook is a deep dive for C# programmers who want to write applications using a single code base that targets the three most popular mobile platforms: iOS, Android, and Windows

Added Dayle Rees's *Laravel: Code Happy* book to the PHP list.

Eases the list lookup. Also added the author name to *Laravel: Code Bright* book.

The "Official Documentation (Offline Version)" Laravel book isn't free.

[Ansible](https://www.ansible.com/) is one of [configuration management tools](https://en.wikipedia.org/wiki/Configuration_management#Operating_System_configuration_management) to install and configure language run-time, server, database or any software in many kinds of operating system.

Added Dayle Rees's PHP Pandas book to the PHP list.

Fixed link in contents page

Linux Inside is a series of posts about the linux kernel and its insides.