Editable Installation Issue Using Pip

I'm currently finding that running `pip install -e . ` as specified in the install instructions doesn't work for python version 3.7.0. I've tried with pip version 10 and also version 23.

I believe that, at least on my machine, the issue is that the editable install pattern assumes there is a `dice_rl` folder in the top level of the repo containing all of the package code, rather than the package code/module folders being present at the root level of the repo. Locally adding a `dice_rl` folder and moving the contents of the package into it appears to have made `dice_rl` importable, where before attempting to import was provoking an `ImportError`.

Start with the installation instructions and reproduce `pip install -e .` using Python 3.7.0 and the reported pip versions. Inspect the repository root and package layout to determine why `dice_rl` is not importable; done means the documented editable install succeeds and the package imports without manually moving folders.

Written by the indexing model from the issue text.