Add additional examples

Author: gjbex

source-code/README.md

@@ -26,3 +26,5 @@ was used to develop it.
    demonstrates `mypy`.
 1. `unit-testing`: illustrates writing unit tests with `unittest` and
    `pytest`.
+1. `oo_vs_functional.ipynb`: comparing object-oriented approach to
+  functional approach, including coroutines.

source-code/iterators/README.md

@@ -42,3 +42,4 @@ often they can be constructed by using the Python standard library's
 1. `generating_data.py`: a retake of the data geenration script in
     Fundamentals, now using `itertools` and built-in Python functional
     features.
+1. `iterators_vs_generators.ipynb`: comparing iterators to generators.