pygame into requirements

[miguelgondu]

Hi,

First of all, thanks for maintaining pyvgdl.

This is the first of two issues I want to bring to your attention.

It seems that pygame is required to run py-vgdl, of course, but it isn't in the requirements.txt.

I just cloned your repo, installed it in a clean conda environment of Python 3.6 with pip install -e '.[all]', and when trying to run python -m vgdl.util.humanplay.play_vgdl vgdl/games/aliens_lvl0.txt I ran into a ModuleNotFoundError, saying pygame should be installed.

Cheers.

[rubenvereecken]

Alright that's a good catch. I could simply add it to requirements, but I don't think any version of pygame is compatible. So I'll make work of it, but I need to take a proper look and try out some versions.