Add a model generator

[ClementBeal]

Hi!

I just tried your tool and it's very great! I was wondering if it was possible to add a generator command line like in Ruby on Rails.

It would be something like genq generate User to generate the user.dart file with the basic template like in your README.

It would be useful to have this feature because there's no VSCode extension or snippets for that.

[jankuss]

I think this would be better suited in our planned editor integrations (#13), instead of the CLI. There we have the ability to define snippets, which should be a superior experiennce.