title: Git submodule add: "a git directory is found locally" issue
body: <p>I'm actually trying to learn how to use git, including the <code>git submodule</code> subcommands.
  I already set up a server on which I can host, push and pull git repositories by using SSH.
  I created a main git repository "Travail" on this server in which I would like to put all my projects as submodules.</p>
  
  <p>In my Travail repository, I already added a project of mine as a submodule at <code>tools/libft</code>:
  I'm able to develop this submodule, to push and to pull it.</p>
  
  <p>But when I try to add another submodule (named fdf, from fdf.git on my server), I get the following issue :</p>
  
  <pre><code>git submodule add ssh://XXX.XXX.XXX.XXX:XXXXX/opt/git/fdf.git projets/fdf
  </code></pre>
  
  <blockquote>
    <p>A git directory for 'projets/fdf' is found locally with remote(s):
          origin    ssh://git@XXX.XXX.XXX.XXX:XXXXX/opt/git/fdf.git
        If you want to reuse this local git directory instead of cloning again from
          ssh://XXX.XXX.XXX.XXX:XXXXX/opt/git/fdf.git
        use the '--force' option. If the local git directory is not the correct repo 
        or you are unsure what this means choose another name with the '--name' option.</p>
  </blockquote>
  
  <p>There is actually no subdirectory in <code>projets/</code></p>
  
  <p>I read on another thread that I should use <code>git submodule sync</code> or edit the .gitmodules file in which the URL to my submodule's origin repository could have changed.</p>
  
  <p>But my .gitmodules file only contains the information about my first submodule (tools/libft), not about projets/fdf :</p>
  
  <pre><code>[submodule "tools/libft"]
      path = tools/libft
      url = ssh://git@XXX.XXX.XXX.XXX:XXXXX/opt/git/libft.git
  </code></pre>
  
  <p>As a French student I could have missed something in the English documentation I have, but I searched and I really don't understand why I get this issue.</p>
  
  <p>I would be glad if I would get a solution but just an explanation would be helpful too.</p>