enable rendering of Mermaid diagrams (used in Overview of ROCm ecosystem)

Author: boegel

mkdocs.yml

@@ -112,7 +112,11 @@ markdown_extensions:
   # support for using MarkDown in HTML
   - md_in_html
   # code blocks with syntax highlighting, graphs
-  - pymdownx.superfences
+  - pymdownx.superfences:
+      custom_fences:
+        - name: mermaid
+          class: mermaid
+          format: !!python/name:pymdownx.superfences.fence_code_format
   # line numbers
   - pymdownx.highlight:
       anchor_linenums: true