Add Contributing section about gallery examples (pvlib#905)

* add section about gallery examples to contributing guide

* whatsnew

* whatsnew cleanup

* add review suggestion

Author: kandersolar

docs/sphinx/source/contributing.rst

@@ -254,6 +254,40 @@ To build the docs locally, install the ``doc`` dependencies specified in the
 `setup.py <https://github.com/pvlib/pvlib-python/blob/master/setup.py>`_
 file. See :ref:`installation` instructions for more information.
 
+Example Gallery
+---------------
+
+The example gallery uses `sphinx-gallery <https://sphinx-gallery.github.io/>`_
+and is generated from script files in the
+`docs/examples <https://github.com/pvlib/pvlib-python/tree/master/docs/examples>`_
+directory.  sphinx-gallery will execute example files that start with
+``plot_`` and capture the output.
+
+Here is a starter template for new examples:
+
+.. code-block:: python
+
+    """
+    Page Title
+    ==========
+
+    A sentence describing the example.
+    """
+
+    # %%
+    # Explanatory text about the example, what it does, why it does it, etc.
+    # Text in the comment block before the first line of code `import pvlib`
+    # will be printed to the example's webpage.
+
+    import pvlib
+    import matplotlib.pyplot as plt
+
+    plt.scatter([1, 2, 3], [4, 5, 6])
+    plt.show()
+
+For more details, see the sphinx-gallery
+`docs <https://sphinx-gallery.github.io/stable/syntax.html#embedding-rst>`_.
+
 .. _testing:
 
 Testing

docs/sphinx/source/whatsnew/v0.7.2.rst

@@ -42,8 +42,9 @@ Bug fixes
 
 Documentation
 ~~~~~~~~~~~~~
-* Add NumFOCUS affiliation to Sphinx documentation :pull:`862`
-* Add example of IV curve generation :pull:`872`
+* Add NumFOCUS affiliation to Sphinx documentation (:pull:`862`)
+* Add example of IV curve generation (:pull:`872`)
+* Add section about gallery examples to Contributing guide (:pull:`905`)
 
 Requirements
 ~~~~~~~~~~~~