wrong symbol for year

Signed-off-by: Vanessa Sochat <[email protected]>

Author: vsoch

_includes/footer.html

@@ -22,7 +22,7 @@
       <div class="md-footer-copyright">
 
           <div class="md-footer-copyright__highlight">
-            Copyright &copy; {{ site.time | date: '%y' }} - {{ site.author }}
+            Copyright &copy; {{ site.time | date: '%Y' }} - {{ site.author }}
           </div>        
       </div>