Missing Drupal module dependency installer

Problem/Motivation

A modules dependencies might be info info.yml but not it's composer.json file. This is also problem with sub-modules.

Steps to reproduce

Proposed resolution

Alter the module install form with a "Install dependencies" link for each module where the dependencies are missing.

Would need to extend \Drupal\package_manager\StageBase with something DependencyInstallerStage

Remaining tasks

User interface changes

API changes

Data model changes