Formatting fixes:
Added empty line before heading "Information Retrieval" to fix html output.
Untabified one line in Python section.
remove broken macruby link
Merge pull request #445 from shelleyvadams/master

Formatting fixes:
Merge pull request #446 from eellson/remove-dead-link

remove broken macruby link
Initial removal of english books from chinese(zh) books list.
Removal decisions were made comparing it with the english(en) books list; itens with the exact same link were removed.
Further removal may need a more careful consideration, since for some reason these book's titles were translated to chinese in the *zh* list.
Added 3 chinese(zh) books.
Berkeley link doesn't require signup
Add french book "Calcul mathématique avec Sage", collectif
Merge pull request #450 from ericguirbal/fr

Add french book "Calcul mathématique avec Sage", collectif
Merge pull request #448 from hiisi13/master

Algorithms - Berkeley link doesn't require signup
Add Explore Flask book (crowdfunded)
Merge pull request #451 from JIghtuse/master

Add Explore Flask book (crowdfunded)
Add a ruby on rails metaprogramming book

Added "Kestrels, Quirky Birds, and Hopeless Egocentricity" under the Ruby on Rails.
Merge pull request #452 from sbagdat/patch-1

Add a ruby on rails metaprogramming book
Added two Tcl books
Merge pull request #453 from tpoindex/patch-1

Added two Tcl books
Added "A Course in Machine Learning"
Merge pull request #454 from bbuyukguzel/master

Added "A Course in Machine Learning"
Add Arduino
Merge pull request #455 from hiseba/patch-1

Adding Arduino
Add a coffeescript book