Added SVG fallback to apps settings popup

This fix issue of calendar app with IE8, see issue report for details:
https://github.com/owncloud/calendar/issues/291

core/js/js.js

@@ -416,6 +416,11 @@ var OC={
 							throw e;
 						});
 					}
+					if(!SVGSupport()) {
+						replaceSVG();
+					} else {
+						SVGSupport.checkMimeType();
+					}
 				}).show();
 			}, 'html');
 		}