title: When is it required to call git_remote_update_tips?
body: <p>I've been playing with git fetch functionality similar to the <a href="http://libgit2.github.com/libgit2/ex/HEAD/fetch.html" rel="nofollow">fetch example</a> for libgit2, but I'm running into some issues. The example as provided does not seem to work for me. Specifically, <code>git_remote_update_tips</code> returns -1 and <code>giterr_last</code> indicates that this is because I have disconnected from the remote. I tried reordering the calls so <code>git_remote_update_tips</code> comes first, but that results in an access violation.</p>
  
  <p>I'm finding the API documentation and the source code to be not very illuminating for me in this regard - I'm just wondering if there is a guideline or good explanation somewhere for exactly what this function does and when I need to call it.</p>