Include implementation of dropboxstorage from Cedric Leninivin

test/tests.html

@@ -29,6 +29,7 @@
   <script src="jio.storage/indexeddbstorage.tests.js"></script>
   <script src="jio.storage/unionstorage.tests.js"></script>
   <script src="jio.storage/querystorage.tests.js"></script>
+  <script src="jio.storage/dropboxstorage.tests.js"></script>
 
   <!--script src="../lib/jquery/jquery.min.js"></script>
   <script src="../src/jio.storage/xwikistorage.js"></script>