TODO

* Better __namespace__ decleration
    Two model can have same __namespace__,
    consider one model was built in, but one day we decided to split it out
    into another service, so all related data need to be pulled from remote,
    Then we can use a model with same __namespace__ to replace it, but hook
    the loading progress, we a instance was loaded, it pulls the data needed
    automatically (or lazyly)

* Better remote support
    Still the above satuation, if we need to handle both "remote" and "local"
    models? Use sub mapper?

* Better Serializer
    So we don't have to declare all needed column/key in each API module.

* Better Proxy decleration
    Model can declera the proxy parameters, like creator, collector.

* Internal event subscribe
    Allow plugin / models to listen on some event, consider just use sqlalchemy's event.
    Implement a internal event bus?

* External event subscribe
    Allow plugin / models to listen on some kind of bus, and hook some functions.

* UI event push
    UI be ware of something is happending, use WS.

* Composive Proxy Helper

* Add local index on accessing non-existing remote object / Build index at beginning

* Dependency Injection of Models
    One entity deps another entiry that provides some feature/columns.

* Interface
    Test result interface, each class inherits it provides sth.

* Bus
    Bus communication between plugins

* Problem
    Flask is not suitable for so many async jobs, but extremely suitable for ORM.
    May encounter proformance issue, in the far future.

* Initializing order
    Entity after attribute / required and provide

* Frontend store / bus

* Frontend path/event dependency
    When a component calls $bus.emit(But not avaliable yet) or store.commit/action
    Maybe instead of throw exception when calling, could perform a check at startup

* Plugins
    The plugin model is very simple, just plain import, has some drawbacks like lack of
    control of plugins, plugins shares everything so it's diffcult to track.
    But make it easy to move any api/components in/out, UI is components so not hard to
    move too.

* CSRF

* Read theme and layout from cookie

* SocketIO for delay

* Event

* UUID for Config, config in store, and dynamic config update

* Cache for entity method with keyword not working

* Update README about Celery worker and Redis backend setup