Project requires drupal/drupal

Problem/Motivation

When importing this project via Composer, it brings drupal/drupal:^7 with it, although it does not need it for its library usage.

Conversely, it is not directly usable at this point, because the engine is built using Drupal 7 autoloading instead of PSR/4, so the application using it needs to update its autoload_files one way or another.

Steps to reproduce

• Add "https://packages.drupal.org/7" to the repositories list in a PHP project
• composer require drupal/grammar_parser
• observe drupal/drupal latest 7.x version being downloaded

Proposed resolution

Provide a composer.json file to allow automatic generation by packages.drupal.org/7.

Remaining tasks

Do it.

User interface changes

None.

API changes

Autoloading becomes available.

Data model changes

None.