Bug fixes

Documentation fixes (it's drush webpack:serve, not yarn :)).
Refactoring. The Libraries trait has been split into 3 separate services. Bundling has been decoupled from Drush, so maybe we can get rid of this dependency at some point.
Added the ability to configure the port of webpack:serve.

Important changes from previous alpha releases

Split into separate projects

This module no longer provides any implementations of processor plugins. They have all been moved into other projects, also hosted on Drupal.org.

You may need to add additional modules to your existing codebase when upgrading to alpha 4. The modules you may need to add are: