userman back: provide '/view/Userman.js' for reloading
um view.Userman: how to use view with fast loading config
extjs_load App.create(): define classes only (and only) once

add Ext.Msg when misused
ENJSMS app_module: use safer `constrainTo` instead of `renderTo`

simplify launching
views: use classes instead of names in strings; coding style

* they are available already, otherwise it will show
wrong dependency if will not work

* coding to match hashes visually
* Desktop: `initComponent()` has no args to pass
App.view.Window: class name; constrainTo; controller; help tool

* controller needs no view config
userman: use safer `constrainTo` instead of `renderTo`; class names

fixes issues with positioning below top bar
fix dynamic reloading of classes for developent

Classes:
- controllers (e.g. 'App.userman.Chat'),
- slow view:
   Ext.define('App.view.Chat',...)
- and fast view definitions (config only):
   App.cfg['App.view.Userman'] = { ... }

* `view.Chat` error after destroy + launch was:

Uncaught TypeError: Cannot read property 'addCls' of null

Thus for dynamic reloading of components all items
must be declared, but not created!