message: Save state between sessions
  Adds: duration, refreshInterval and graph.layout
diff: @@ -39,13 +39,19 @@ const namespacePersistFilter = whitelistInputWithInitialState(
  INITIAL_NAMESPACE_STATE
  );
  -const graphPersistFilter = whitelistInputWithInitialState('graph', ['filterState'], INITIAL_GRAPH_STATE);
  +const graphPersistFilter = whitelistInputWithInitialState('graph', ['filterState', 'layout'], INITIAL_GRAPH_STATE);
  +
  +const userSettingsPersitFilter = whitelistInputWithInitialState(
  + 'userSettings',
  + ['duration', 'refreshInterval'],
  + INITIAL_USER_SETTINGS_STATE
  +);
  const persistConfig = {
  key: persistKey,
  storage: storage,
  - whitelist: ['namespaces', 'jaegerState', 'statusState', 'graph'],
  - transforms: [namespacePersistFilter, graphPersistFilter]
  + whitelist: ['namespaces', 'jaegerState', 'statusState', 'graph', 'userSettings', 'messageCenter'],
  + transforms: [namespacePersistFilter, graphPersistFilter, userSettingsPersitFilter]
  };
  const composeEnhancers =
  