Add README to tutorial (#71)

This gives a rough guided tour of how the tutorial is intended to be
used; basically allowing someone to replay the tutorial as given at the
OMSF workshop.

Author: dwhswenson

rbfe_tutorial/README.md

@@ -0,0 +1,27 @@
+# OpenFE RBFE Tutorial
+
+This tutorial is a recommended starting place for working with OpenFE. This
+tutorial consists of 2 stages: first, there is the command line tutorial, where
+you will work with the OpenFE command line interface (CLI) to set up a
+simulation campaign, see how to run each simulation with the CLI, and then
+gather results from a previously-run simulation into a final table. The second
+stage uses a Jupyter notebook to perform the exact same setup as the CLI, but
+shows how you have more flexibility when working with the Python interface.
+
+## Step-by-step
+
+1. To get an overview of OpenFE, you can view [the slides](https://docs.google.com/presentation/d/12xIu7V-izt-j5nlsPD9IOXih1qm4fPPVwVdulipjSv4/) that were given with
+   this tutorial at the OMSF workshop in May 2023.
+
+2. If you haven't already, install OpenFE using [our recommended install
+   instructions](https://docs.openfree.energy/en/stable/installation.html#installation-with-mambaforge-recommended).
+   We highly recommend installing with `mamba` over `conda`; there is a huge
+   gap in performance.
+
+3. Follow the [CLI tutorial](cli_tutorial.md), which includes downloading the
+   tutorial materials with the `openfe fetch` command.
+
+4. Follow the notebook tutorial, running with `jupyter notebook
+   python_tutorial.ipynb`. The notebook tutorial reproduces the setup stage of
+   the CLI tutorial, but illustrates how you can customize things using the
+   Python API that cannot be customized using the CLI.