Added free eBooks that I am aware of.

I had a blog post here:

http://www.gep13.co.uk/blog/free-ebooks/

which listed some free eBooks that I was aware of.  I have taken the programming related ones, and added them to this list.
Corrected links

Corrected the internal link to the Windows 8 section.
Corrected the external link to Windows Phone Blue Book
Add Html5, CSS and Javascript Book Blog Link
Merge pull request #285 from minsOne/master

Add Html5, CSS and Javascript Book Blog Link
Merge pull request #283 from gep13/master

Added free eBooks that I am aware of.
Merge pull request #284 from maieul/master

Annexe B du LaTeX Companion + remise en ordre alphabetique des titres