Open API Explorer initial proofing ground (#1392)

* stage

* stage

* Allow for dynamic grouping over classification > tag > endpoint > operation, each collapsing if there is only one child

* stage something that works

* better grouping

* list overloads on operationview

* start building out api pages

* Render markdown descriptions

* ci/lint

* ensure global layout is seeded uniformly

* ensure links take url path prefix in to account

* eat urlpath prefix when generating file names

Author: Mpdreamz

docs/_docset.yml

@@ -17,8 +17,9 @@ subs:
 features:
   primary-nav: false
 
+#api: kibana-openapi.json
 api: elasticsearch-openapi.json
-  
+
 toc:
   - file: index.md
   - hidden: 404.md