Add UI for viewing labels on a manifest in the tags view

static/js/directives/ui/label-list.js

@@ -0,0 +1,15 @@
+/**
+ * An element which displays labels.
+ */
+angular.module('quay').directive('labelList', function () {
+  return {
+    templateUrl: '/static/directives/label-list.html',
+    restrict: 'C',
+    replace: true,
+    scope: {
+      expand: '@expand',
+      labels: '=labels'
+    },
+    controller: function($scope) {}
+  };
+});