title: Keep track of the positions of all elements in a jQuery sortable
body: <p>I'm trying to figure out how I can track how the elements in a jQuery sortable.
  Let's say that I have four elements (divs) in my sortable, each have an unique id. Let's call them #100, #200, #300 and #400 and they're presented in that order to start with. But when I move #100 to let's say spot number 3, I need to be able to save the new position for this id, but also make sure that the other ones get updated position values aswell.</p>
  
  <p>Am I making any sense? Basically I want to get the positions of each unique id, so I can save the order of the list for later use.</p>
  
  <p>I haven't been able to find something that reports for all the elements in a sortable, just for the one that was moved..</p>
  
  <p>Point me in the right direction? 
  Thanks</p>