add link to Society6

Well, just for a future me to refer to, at least

contact.html

@@ -3,7 +3,7 @@
 <div>
 <h3>Email
 </h3>
-<p><pre>phtan90#gmail^com</pre>
+<p>phtan90#gmail^com
 <br />replace # with @ 
 <br/>and ^ with .
 </p>
@@ -66,6 +66,11 @@
     An online store where I sell my artwork
     </a>
   </li>
+<li><a href="https://society6.com/tonychen">
+a store where various products feature photos I've taken
+</a>
+(For example: coasters, prints, cases for mobile phones).
+</li>
   <li><a href="http://phtan.newsblur.com/">A news-sharing web-site</a>
     </li>
   <li><a href="https://medium.com/@tanphengheong">Medium.com