Adapt the book for a newest version of Pharo

[jecisc]

When the book will be ported to github it would be good to update the tutorial to a newest version of Pharo. This will need some update on the book as:

• [ ] The workspace was replaced by the playground
• [ ] On Pharo -> Comanche Server: the class of the adaptor changed
• [ ] On Pharo -> Define a Category: Category should be call Package now
• [ ] On Pharo -> Define code: Category is now call protocol