title: How can I import a mercurial repo (including history) into another mercurial repo as a subdirectory, without using subrepos?
body: <p>This sounds kind of complex, so let me explain:</p>
  
  <p>Project_A has lived for some time within its own Mercurial repository. Project_A is now getting folded into a new super project, Super-Project_B.  Super-Project_B also has a mercurial repository. We would prefer if Project_A were not a subrepo, but instead just a normal child, but we also don't want to lose the history.  Is there a way to do this?</p>