Ext.state.Manager: Ext.state.LocalStorageProvider

there were problems on the way with node-webkit and JSDuck, all is OK now
`ns` userman: provide own namespace to some components

* view.Window: support `ns` in development reloads
* um/view/Userman (items_*): `ns`
* app_back_userman: provide `view.Userman` under `ns` with
  auth check involved (modify 408123accf5d839264c4925bdcd2ff01a2390fae)
static files fixes: app.htm user-offline.png

* root and app.htm are OK with static mw
* user-offline.png: when network interface goes down,
  this image may not be available via HTTP, thus base64 it in css