fixed pixel ratio issue with buffer canvas usage

test/runner.html

@@ -90,6 +90,9 @@
     <script src="functional/KineticEvents-test.js"></script>
     <script src="functional/DragAndDropEvents-test.js"></script>
 
+    <!--=============== manual tests ================-->
+    <script src="manual/manual-test.js"></script>
+
     <script>
       if (window.mochaPhantomJS) { mochaPhantomJS.run(); }
       else { mocha.run(); }