Add a build display name, set it from the etag reported by s3 for file uploads.

static/partials/repo-build.html

@@ -19,7 +19,7 @@
         <li ng-class="currentBuild == build ? 'active' : ''" ng-repeat="build in builds">
           <a class="build-tab-link" href="javascript:void(0)" ng-click="setCurrentBuild(build.id, true)">
             <span class="phase-icon" ng-class="build.phase"></span>
-            <span>{{ getShortId(build.id) }}</span>
+            <span>{{ build.display_name }}</span>
           </a>
         </li>
       </ul>