[glossary] Glossary MVP (#4865)

* [glossary] Glossary MVP

* resolve conflict

* initial pass at includable glossary data

* tag to term mapping

* Change StatefulSets to singular, StatefulSet

* revise glossary style guide, move

* make descriptions plural

Makefile

@@ -15,4 +15,4 @@ serve: ## Boot the development server.
 	jekyll serve
 
 stage: ## Run the Jekyll staging container.
-	docker run -ti --rm -v "$PWD":/k8sdocs -p 4000:4000 gcr.io/google-samples/k8sdocs:1.1
+	docker run -ti --rm -v "${PWD}":/k8sdocs -p 4000:4000 gcr.io/google-samples/k8sdocs:1.1