Feature: `forFeature` to define models in other modules

[Alexnortung]

In Nestjs a module can have a forRoot static function which the mindsdb module has in this project. However some of these modules can also be called with the forFeature static method to add only a couple of new parts. A good example is the typeOrm module. Docs

I would like something similar, such that I can have my main configuration of mindsdb in one module and in some sub modules I can define different models that are associated with what the module is doing.

[danshapir]

Feel free to open a pull request.