Review of 'Coding in the debugger' chapter complete
Merge pull request #5 from bencoman/Chapter7-CodingInDebugger

Review of 'Coding in the debugger' chapter done.
Merge pull request #7 from bencoman/Chapter8-ImprovingOurModel

Chapter 8, rename case sensitive filename
Review of Chapter 9 'Enhancing MirrorCell'
Merge pull request #8 from bencoman/MirrorCell

Review of Chapter 9 'Enhancing MirrorCell'
Correct typos in a variable name and a method name.