title: There is no package named "CLACK.APP.DIRECTORY"
body: <p>I am learning about Common Lisp and the <a href="http://clacklisp.org/" rel="nofollow">Clack</a>, following the tutorial:</p>
  
  <p><a href="http://clacklisp.org/tutorial/06-using-clack-app-directory.html" rel="nofollow">http://clacklisp.org/tutorial/06-using-clack-app-directory.html</a></p>
  
  <p>But in this chapter(Using Clack.App.Directory) I can't success, the SLIME prompts error: "There is no package named "CLACK.APP.DIRECTORY" "</p>
  
  <p>But I followed all the steps in the tutorial, is there anything I missed? I am noob in lisp BTW.</p>