feat: Allow for the creation of a feature module that is not associated with an app

[bjornharvold]

The use case is very helpful for very large domains with many reactive entities. The module tends to become large when it could be separated into separate features.

Example:

apps:
   - my-app
libs:
   - my-app
      - domain
      -    +state
      -       feature-1
      -       feature-2
      -       feature-100
      - feature-1
      - feature-2
      - feature-100

Instead:

apps:
   - my-app
libs:
   - my-app
   -    domain -> +state
   -    feature-core-1
   -    feature-core-2
   - my-app-feature-1
   -    domain -> +state
   -    feature-1-create
   -    feature-1-update
   - my-app-feature-2
   -    domain -> +state
   -    feature-2-create
   -    feature-2-update
   - my-app-feature-100
   -    domain -> +state
   -    feature-100-create
   -    feature-100-update

All feature libraries would depend on domain and parent domain modules:

MyAppFeature100CreateModule {
  imports: [CommonModule, MyAppDomainModule, MyAppFeature100DomainModule]
}

Thoughts on this appreciated. I want to avoid creating ui modules and then rename them to feature because they contain reactive code.

Cheers on a great plugin!

[manfredsteyer]

The next version (2.0.0) will have a --no-app switch for this.