Update free-courses-en.md
Duplicate Haskell Entry
MATLAB to Alpha order
PHP -> Alhpa Order
SQL Server -> Alpha Order
GitHub Cheat Sheet - Tim Green
Fix typo
Remove dead link
Remove outdated Django Book
[en] Sorting MATLAB section
Update URL for Rust by Example
Correct a link
Merge pull request #964 from esparta/master

[en] Sorting MATLAB section
revised..

Removed Books and added some more Courses..
Update free-courses-en.md
[en] Adding misc. book
Merge pull request #965 from esparta/master

[en] Adding misc. book
Update free-courses-en.md
Update free-courses-en.md
Update free-programming-interactive-tutorials-en.md

Added interactive courses in Python and Ruby..
Added new Section for HTML&CSS and added two courses..