adding readme for python generator. change name to plural

Author: FoamyGuy

python_generator/README.md

@@ -0,0 +1,16 @@
+This folder contains scripts that can be run to create requirement screenshots for all of the learn guide projects
+
+To use the scripts you must set `LEARN_GUIDE_REPO` to point to the learn guide repo.
+
+Then you can run
+
+```
+python get_bundle_data.py
+```
+to download `latest_bundle_data.json`
+
+Once this file is present run
+```
+python create_requirement_images.py
+```
+It will create images in the `generated_images` directory.