Add code from chapter 33 of "Programming in Scala" as tests

[Philippus]

It would be nice to add the bits of code from chapter 33 of "Programming in Scala" as tests to be sure we don't break compatibility (too much) with the book.

[SethTisue]

@bvenners do you plan to retain that material in the upcoming 2.13 edition?

[doehyunbaek]

Hi. It seems like this chapter got moved to advanced_programming_in_scala instead. Do you think it would be better to implement test from old books(2e,3e,4e ch33) or new book still in preview(ch11)

[Philippus]

I'd say from the new book.