Update index.html

Updates notes on example slide deck

examples/index.html

@@ -150,7 +150,7 @@
                     <img class="r-stretch" src="https://mymodernmet.com/wp/wp-content/uploads/2017/09/dog-portraits-alexander-khokhlov-2.jpg">
 
                     ### Notes:
-                    Vertical slides also need to be stretched to fit
+                    Vertical images also need to be stretched to fit
 
                     Markdown Code for this slide:
                     ```