calendar.md: Move doc text to the top of page

calendar.md

@@ -7,16 +7,16 @@ description: An embedded Google Calendar displaying the weekly event schedule.
 
 # Course Calendar
 
-{% for module in site.modules %}
-{{ module }}
-{% endfor %}
-
----
-
 Course materials are defined in the `_modules` directory. Each module is rendered here according to their filename.
 
 Modules are rendered according to the layout file defined in `_layouts/module.html`. Edit the HTML to modify the layout.
 
+## Modules
+
+{% for module in site.modules %}
+{{ module }}
+{% endfor %}
+
 ## Table Calendar
 
 We can also render modules as HTML tables. Modify `_includes/module_table.html` to make changes.