title: how to update existing shelve set in tfs
body: <p>My team is using shelving for code review, for X++ code. Which is not a native visual studio language. So you can consider like we storing text files in TFS. </p>
  
  <p>For code developer create a shelve and send it over to the team to reviews it and send feedback. But when the developer address the comments and generates another shelve the comments are lost. </p>
  
  <p>For the reviewer，it becomes difficult if there original comments were addressed or not.  The only way is compare 2 shelve code on 2 screen, which is a pain.</p>