Rearrange the page order in a proof

[#1]

Description - user generates a proof only to then notice the order of the pages is wrong. Would be nice if instead of deleting that version, the user could simply rearrange the page order within the proof. 

Why is this feature important to you - it would save time; would function like Acrobat 

How would you like the feature to work - drag & drop. open to other ideas tho. 

Current Behaviour - user needs to delete the version in question & upload a new, reordered version.