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revised..

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

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

Added interactive courses in Python and Ruby..
Added new Section for HTML&CSS and added two courses..
Merge pull request #960 from avinoth/patch-1

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2 line after each Section