Merge pull request googlearchive#41 from mbleigh/order-by-value

Adds orderByValue (new feature of Firebase 2.2)

bower.json

@@ -3,6 +3,6 @@
   "private": true,
   "dependencies": {
     "polymer": "Polymer/polymer#master",
-    "firebase": "^2"
+    "firebase": "^2.2"
   }
 }

firebase-element.html

@@ -213,6 +213,12 @@ <h3>My Firebase Data</h3>
        * @type Boolean
        */
       orderByPriority: false,
+      /**
+       * Specify to order by value the set of records reflected on the client.
+       * @attribute orderByValue
+       * @type Boolean
+       */
+      orderByValue: false,
       /**
        * Specify to create a query which includes children which match the specified value. The argument type depends on which orderBy*() function was used in this query. Specify a value that matches the orderBy*() type.
        * @attribute equalTo
@@ -302,6 +308,9 @@ <h3>My Firebase Data</h3>
         if (this.orderByPriority) {
           query = query.orderByPriority();
         }
+        if (this.orderByValue) {
+          query = query.orderByValue();
+        }
         if (this.equalTo) {
           query = query.equalTo(this.equalTo);
         }