How can I select multiple images when uploading them to a website?
first Step :

When you open the Gallery, you should see three soft keys at the Button, Share, Delete and More.

Click Share and you should get a pop-up menu. Select your method of sharing. Now, you should see little check boxes in the upper right hand corner of each pic.
 Check whichever pics you want to send. Deleting multiple pics works the same way, except obviously you'd select "Delete" instead of Share.

Example :



Also, this feature maybe added in latest Rom, you need to try it.this reply just for give you more information and acquaintance.

good day.