title: Can Firebase entries include commas in their names?
body: <pre><code>var ref1 = new Firebase("http://gamma.firebase.com/myuser/123,456");
  ref1.set("123,456");
  var on1 = ref1.on("value", function(snapshot) {
      console.log(snapshot.val());
  });
  // console logs 123,456
  </code></pre>
  
  <p>So naming with a comma works fine. But let's say you want to pass around the url to the ref.</p>
  
  <pre><code>var url1 = ref1.toString();
  console.log(url1);
  // console logs http://gamma.firebase.com/myuser/123%2C456
  </code></pre>
  
  <p>The toString() function returns a version of the url with commas replaced by "%2C". This would be fine if the URL were still useable.</p>
  
  <pre><code>var ref2 = new Firebase(url1);
  var on2 = ref2.on("value", function(snapshot) {
      console.log(snapshot.val());
  });
  // console logs null
  </code></pre>
  
  <p>Is this a bug, or is there a good reason why the user should have to do something like</p>
  
  <pre><code>var url1 = ref1.toString().replace(/%2C/g,",");
  </code></pre>
  
  <p>in order to get a useable Firebase URL?</p>