title: Whats the Proper usage of .gitattributes with merge=ours
body: <p>I just tried using .gitattributes for the first time.  I figure I must be doing something wrong because it is not working as I thought the purpose of using the <code>merge=ours</code> attribute was intended for (?).</p>
  
  <p>An example of my usage:</p>
  
  <p>I have two branches; one is the "master" and the other is "GCE-Site". There are files on the "GCE-Site" branch that have different settings that also exists on the "master" branch that I do not want merging into the "master" [or other branches].</p>
  
  <p>On both branches, I have a <code>.gitattributes</code> containing the following rules:</p>
  
  <pre><code>README.md merge=ours
  config.php merge=ours
  .gitattributes merge=ours
  .gitignore merge=ours
  .cache/ merge=ours
  </code></pre>
  
  <p>All the files needing the rules are on the root level plus everything above the .cache/ folder. When I do a <code>git merge GCE-Site</code>, all files still merge into the master when I don't want that.  </p>
  
  <p>Is there something I am missing? Your help is greatly appreciated. Thnx</p>