Updated Pharo Chapter 2 ready for review

Hi

yes it is long and tedious.
Now the second chapter is ready for review. Should work with Playground,
new debugger and spotter.
Thanks in advance.

Stef


https://ci.inria.fr/pharo-contribution/view/Books/job/UpdatedPharoByExample/234/artifact/book-result/PharoTour/PharoTour.pdf