title: git: change origin of cloned submodule
body: <p>I created a project <code>submodule</code> and put it up on Github.</p>
  
  <p>I created another project, <code>supermodule</code>, and then did this:</p>
  
  <pre><code>cd supermodule
  git init
  mkdir lib
  git clone git://github.com/tandu/submodule lib/submodule
  git submodule add ./lib/submodule lib/submodule
  </code></pre>
  
  <p>This worked fine, but on the website, it can't find the link to the submodule when viewing the files (in fact it just says "Loading Commit data" forever).  The submodule folder itself has the correct <code>origin</code>.</p>
  
  <p>Apparently, what I should have done was</p>
  
  <pre><code>...
  mkdir lib
  git submodule add git://github.com/tandu/submodule lib
  </code></pre>
  
  <p>...but it's too late for that now.  How can I have the submodule in this project correctly point to <code>origin</code>?</p>