Make image filenames be the date and time of capture

examples/single_chip/camera_web_server/main/www/index_ov2640.html

@@ -717,6 +717,8 @@ document.addEventListener('DOMContentLoaded', function (event) {
     try {
       var dataURL = canvas.toDataURL('image/jpeg');
       saveButton.href = dataURL;
+      var d = new Date();
+      saveButton.download = d.getFullYear() + ("0"+(d.getMonth()+1)).slice(-2) + ("0" + d.getDate()).slice(-2) + ("0" + d.getHours()).slice(-2) + ("0" + d.getMinutes()).slice(-2) + ("0" + d.getSeconds()).slice(-2) + ".jpg";
     } catch (e) {
       console.error(e);
     }

examples/single_chip/camera_web_server/main/www/index_ov3660.html

@@ -744,6 +744,8 @@ document.addEventListener('DOMContentLoaded', function (event) {
     try {
       var dataURL = canvas.toDataURL('image/jpeg');
       saveButton.href = dataURL;
+      var d = new Date();
+      saveButton.download = d.getFullYear() + ("0"+(d.getMonth()+1)).slice(-2) + ("0" + d.getDate()).slice(-2) + ("0" + d.getHours()).slice(-2) + ("0" + d.getMinutes()).slice(-2) + ("0" + d.getSeconds()).slice(-2) + ".jpg";
     } catch (e) {
       console.error(e);
     }