LOYALIST-18 Add Front page carousel section to loyalist core readme

custom/modules/loyalist_core/README.md

@@ -5,3 +5,15 @@ TODO: write some documentation.
 ## Requirements
 
 This module requires no modules outside of Drupal core.
+
+
+## Front Page Carousel
+
+The front page carousel depends on the JS library, Owl Carousel v2.3.4 (see subtheme
+`owlcarousel2` library definition). It relies on `Media | Image` slide content which
+references a <kbd>carousel</kbd> `Tags` taxonomy term.
+
+The carousel itself is implemented by the view, `Loyalist Carousel`, `Owl Block` block
+display. The view depends on the `Views Rows Wrapper` contrib module to provide a
+`Rows Wrapper` formatter to minimize the HTML structure for use by the Owl Carousel
+library.