Update free-programming-books.md

Adding RESTful Web Services book
Added a very good and complete book for Java and added iOS book
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.
Merge pull request #447 from jgpacker/master

Initial removal of english books from chinese(zh) books list.
Update free-programming-books.md
added Twitter share button

I couldn't add a Facebook share button because I don't have an account but here is the link if someone else wants to add it:

https://developers.facebook.com/docs/plugins/like-button/
Merge pull request #459 from breakingcrypto/patch-1

added Twitter share button
Merge pull request #458 from murphyrandle/master

Update free-programming-books.md
Fix and close #449
Add 'Ruby on Rails' section and 'El maldito libro de los Descarrilados' book
merge assembly with "ensamblador"

both catergories are the same. I also put the title of Lisa Watts's book in spanish (as the translations version has)
Merge pull request #462 from mgaitan/patch-1

merge assembly with "ensamblador" (spanish list)
Add index for 'Ruby on Rails' section.
Merge pull request #461 from Chakaitos/master

Update free-programming-books-es.md - new resource
Fixed link to How to be a Programmer
Merge pull request #463 from sugarjig/patch-1

Fixed link to How to be a Programmer
Update free-programming-books-pl.md
Merge pull request #464 from zawieja/master

Update for 'pl' file : Book added: Pisanie OS
Update free-programming-books.md

added "Deep C" under entry of C material.
Update free-programming-books.md

changed "Graphics User Interfaces" into "Graphical User Interfaces"