fixed typo: a -> an

Author: Aaron Beckerman

remotes/index.html

@@ -296,7 +296,7 @@ <h2>
  * [new branch]      erlang -> erlang
 </pre>
 
-    <p>Now when people clone or fetch from that repository, they'll get a 'erlang'
+    <p>Now when people clone or fetch from that repository, they'll get an 'erlang'
     branch they can look at and merge from. You can push any branch to any
     remote repository that you have write access to in this way. If your branch
     is already on the server, it will try to update it, if it is not, Git will