Added the 'How to do what you love & Earn what youre worth as a programmer' book to the 'Professional Development' list.
Added the 'What I have learned from failure' to the 'Professional Development' list.
Added the 'Why programmers work at night' book to the 'Professional Development' list.
Merge pull request #604 from rodrigo-medeiros/master

Added three books to the to the 'Professional Development' list.