Add Channel9's Windows Phone 8.1 Development Guide for Absolute Beginners
Merge pull request #1150 from rickyliang/rickyliang

Add Windows Phone resource
Adding git guide and python for informatics pdf link in tutorials md file
Removing the git link and adding python link in ebook
Merge pull request #1152 from tusharsappal/master

Removing the git link and adding python link in ebooks.md