title: Checking in only parts of files
body: <p>Is it possible to select which changes in a file you want to check in? For example, I have added two projects to a solution file, but I only want to check in one of them.
  Or I have done work in two parts of a file, but only one part is done and ready to check in.
  Ideally, I'd like to use the new diff-utility in 2012, and just select the parts I want to check in, but can I do that?</p>