To let the user control how many levels to show in the navigation tree on the left. <img width="319" alt="image" src="https://user-images.githubusercontent.com/4189262/68554268-436dfb80-041f-11ea-96c1-1144a41f341f.png"> Right now hardcoded to 4. Should be named `navigation_depth` to follow the ReadTheDocs config: https://sphinx-rtd-theme.readthedocs.io/en/stable/configuring.html
To let the user control how many levels to show in the navigation tree on the left.
Right now hardcoded to 4.
Should be named
navigation_depthto follow the ReadTheDocs config: https://sphinx-rtd-theme.readthedocs.io/en/stable/configuring.html