Added the Language Agnostic subsections to TOC

Add Problem Solving with Algorithms and Data Struc

more hackershelf books, some refactoring

Found myself scrolling through the Language Agnostic section a lot; added TOC for quicker access.

Add Problem Solving with Algorithms and Data Structures. Since it is
written in python, I have added it twice.

This was suggested by Fabian Dablander on the Python community on
Facebook.

Add Dart language;
Reorder meta-lists, add O'Reilly Commons and hacker shelf
Remove duplicate (Bayesian Methods for Hackers)
Additions from hackershelf

Put Flask under Python

Adding Octave

Update free-programming-books.md

Added Adobe Flex2 programming book

added french list and 2 books (C, Javascript)

Scientific python 

Add Hadoop Illuminated

Minor changes

Fix "Programming Computer Vision with Python" link

Adding @hadoop-illuminated to the free book list.

scientific python resources

Django is a high-level Python Web framework, therefore, it should be
included as a subsection of `Python`.

Ref: https://www.djangoproject.com/

Added 'Practical File System Design: The Be File System' and a Smalltalk list.

Conflicts:
	free-programming-books.md

Put things from misc into appropriate postitions.
Put a few links into their correct sections, in my opinion.

New category: Theoretical OCmputer Science
(Put stuff about automata,formal languages,computability..etc into it)

Deleted duplicated backbone.js books.

Update free-programming-books.md

Added book to Mathematics section

Added some more books. I've found both of these extremely useful :)

Added book to Datamining section

Introduction to Statistical Thought by Michael Lavine