Apply workaround for floating property fields

The RTD theme has an incompatibility issue with autodoc as both use a
"property" CSS class for different purposes.  Add a custom CSS file with
a workaround to fix this issue.

See readthedocs/sphinx_rtd_theme#1247 for more
information.

mpiis_doc_build/build.py

@@ -511,6 +511,14 @@ def build_documentation(
     with open(doc_build_dir / "conf.py", "wt") as f:
         f.write(out_text)
 
+    # copy the custom.css to _static
+    static_dir = doc_build_dir / "_static"
+    static_dir.mkdir(exist_ok=True)
+    shutil.copy(
+        resource_dir / "sphinx" / "custom.css.in",
+        static_dir / "custom.css",
+    )
+
     #
     # Copy the license and readme file.
     #

mpiis_doc_build/resources/sphinx/conf.py.in

@@ -121,7 +121,12 @@ if not on_rtd:
 # Add any paths that contain custom static files (such as style sheets) here,
 # relative to this directory. They are copied after the builtin static files,
 # so a file named "default.css" will overwrite the builtin "default.css".
-# html_static_path = ['_static']
+html_static_path = ['_static']
+
+# path is relative to html_static_path
+html_css_files = [
+    'custom.css',
+]
 
 # Custom sidebar templates, must be a dictionary that maps document names
 # to template names.

mpiis_doc_build/resources/sphinx/custom.css.in

@@ -0,0 +1,4 @@
+/* Workaround for https://github.com/readthedocs/sphinx_rtd_theme/issues/1247 */
+dl.py.property {
+    display: block !important;
+}