Remove header from demonstrations section

Remove header from demonstrations section in index.md

Author: staleycyn

index.md

@@ -21,7 +21,7 @@ Scroll down for demonstrations.
 ## Demonstrations 
 
 {% assign demos = site.pages | where_exp:"page", "page.url contains '/Instructions/Demos'" %}
-| Demonstration |
+|  |
 | --- | 
 {% for activity in demos  %}| [{{ activity.demo.module }}]({{ site.github.url }}{{ activity.url }}) |
 {% endfor %}