Add numpy and beautifulsoup4 to setuptools required packages

[gregnordin]

When I installed moodlexport in a fresh virtual environment and tried to run the example notebooks I found that these 2 packages were not installed so I have added them to setup.py so that others don't run into the same problem.

[Guillaume-Garrigos]

Forgetting beautiful soup was a stupid mistake! For numpy though, I've always worked with Anaconda, so I believed it was part of the default installation of python. Good to know it is not.

I'm going to add those changes and it'll be available on pypi in a few minutes.

[gregnordin]

Thanks!

I used to mostly just use Anaconda, but developed some problems over a period of several years. The problems are explained under the "Motivation" heading of the README.md at My Python Setup, as well as how I changed my approach to use specific virtual environments for most of my projects that have just the packages I need for the project. They are easy to tear down and rebuild as needed. I have found this to be a very effective way of managing and using my installed python versions.