title: Git repository within Git repository
body: <p>I have a main git repository A and we are using sources out of another git repository B in a subdirectory of our main project.
  Now it would be good to have the B repository checked out within the A repository in this used subdirectory.
  If someone else then clones the repository of course he should get our main repository A and within that automatically the B repository.</p>
  
  <p>Let me visualize the directory structure:<br /></p>
  
  <pre>
  + main_repository       - the root directory of the main Repository
    + src                 - directory containing the source 
      + foreignRepo       - this should be the root directory of another git repo
    + binaries
    + other
  </pre>
  
  <p>This must be also known in the remote repository, just a local copy doesn't help me, because other people check this out and must be able to compile all the stuff.</p>