Housekeeping (officemix goes into its own subdirectory).

officemix/officemix.html

@@ -7,7 +7,7 @@
 
     <script src="https://appsforoffice.microsoft.com/lib/1.1/hosted/office.js" type="text/javascript"></script>
     <script src="https://labsjs.blob.core.windows.net/sdk/LabsJS-1.0.4/labs-1.0.4.js" type="text/javascript"></script>
-    <script src="./officemix.js" type="text/javascript"></script>
+    <script src="../build/officemix.js" type="text/javascript"></script>
     <style>
         html, body{
             height: 100%;