(Proposal) Default constructor with arguments

I believe allowing constructors with arguments to be default would save us a lot of typing and dead-weight code space.

```
class FieldModel {
FieldModel(Map data) {
...
}
}

class SealerModel extends FieldModel {
// SealerModel(Map data) : super(data);
}
```

Instead of the compile error I'd like that constructor to be picked up and used as default for the subclass.

`error: The superclass 'FieldModel' doesn't have a zero argument constructor. (no_default_super_constructor_implicit at ...`

Start with the constructor examples and the no_default_super_constructor_implicit diagnostic in the issue. Determine whether implicit subclass constructors may forward superclass arguments, then document the accepted semantics and resulting diagnostics; no file or test is named in the payload.

Written by the indexing model from the issue text.