Update free-programming-books.md
Merge pull request #1016 from vamseeps/patch-1

The Codingus
Added Explore Flask by Robert Picard
Merge pull request #1017 from yaph/exploreflask

Added Explore Flask by Robert Picard
Add Java(Spring/Spring Boot/Spring Security) Docs.
Merge pull request #1018 from sudoyu/patch-1

Add Java(Spring/Spring Boot/Spring Security) Docs.
books about software testing
Add Machine Learning docs in Japanese.
Merge pull request #1020 from sudoyu/patch-2

Add Machine Learning docs in Japanese.
Update free-courses-en.md

Added Python course by MIT
Update free-courses-en.md

Added Python course from MIT OCW
Merge pull request #1021 from mousebaiker/master

Python course by MIT
Advertise new search engine
Fix typo
Added 4 Python books and fixed 1 Python book name

Added the following free Python eBooks:
- Learn to Program Using Python ~ By Cody Jackson
- Python Scripting for Computational Science ~ By Hans Petter Langtangen
- Design Patterns In Python ~ By Rahul Verma, Chetan Giridhar 
- Practical Programming in Python ~ By Jeffrey Elkner

Changed "A Beginner's Python Book" to it's proper title: "A Beginner's Python Tutorial"
Merge branch 'master' of github.com:ArnoldM904/free-programming-books into ArnoldM904-master

Conflicts:
	free-programming-books.md
Write Yourself a Scheme in 48 Hours
Fix formatting
Remove dead link
Remove dead link