Adding some of my practice C programs
Merge remote-tracking branch 'origin/master'
Updating the readme
Adding some chapter 5 exercises
Adding Beersong, TurkeyTimer, and ClassCertificates
Adding chapter 5 exercises and challenge
Chapter 6 exercise
Adding chapter 7 exercises
Adding chapter 7 exercises
Chapter 8 exercises
Fixing readme
Adding readline support to CountDown
Adding chapter 9 exercises
removing xcode projects from git