docs: tune RTD to display lists with disc and left margin

RTD default theme removes discs from the section list items which makes
design pages look strange. Add them back via small CSS override.
Also, add 1em on the left side of the disc to provide visual cue that
this is a list item.

Signed-off-by: Alexander Bokovoy <abokovoy@redhat.com>
Reviewed-By: Francisco Trivino <ftrivino@redhat.com>
Reviewed-By: Sumit Bose <sbose@redhat.com>
(cherry picked from commit 79a4073730)

doc/_static/css/ipa.css

@@ -0,0 +1,4 @@
+section ul.simple li {
+    list-style: disc;
+    margin-left: 1em;
+}

doc/conf.py

@@ -72,7 +72,11 @@ html_theme = 'default'
 # 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']
+
+html_css_files = [
+    'css/ipa.css',
+]
 
 # -- Options for sources -----------------------------------------------------