Fix/re-introduce custom Jekyll tags for better glossary integration (#6163)

_data/glossary/_example.yml

@@ -1,5 +1,6 @@
 id: _example
 name: Example K8s Term
+full-link: kubernetes.io/docs/link-to-long-dedicated-docs-page
 aka:
 - Slang K8s Term
 - Misnomer
@@ -10,8 +11,17 @@ related:
 - id-of-commonly-used-with-term
 tags:
 - Some Tag
-short-description: |
-  Required. One or two lines that provide a minimum definition. Do not repeat the term. Write about the plural of the term. Prefer fragments. Model after tooltips. End with a period.
-long-description: |
-  Optional. Longer additional text to appear after (in conjunction with) short description. Provide where the short description is not sufficient as the intro paragraph to a topic. Write complete but concise sentences.
+short-description: >
+  Required.
+  Markdown allowed (e.g. for cross-linking).
+  One or two lines that provide a minimum definition.
+  Do not repeat the term.
+  Prefer fragments.
+  End with a period.
+long-description: >
+  Optional.
+  Markdown allowed.
+  Longer additional text to appear after (in conjunction with) short description.
+  Provide where the short description is not sufficient as the intro paragraph to a topic.
+  Write complete but concise sentences.
   **See /_includes/templates/glossary/README.md for the official style guide.**