8.x-1.3

Added

• Added GrumPHP + code quality tools configuration.
• Added TravisCI script to automatically validate the code quality.
• Added the Drupal 9 compatibility check.

Fixed

• DMOH-57: Fixed broken entity form serialization due to manually injecting the
  Logger instance into the OpeningHoursWidget.
  Is now replaced by use LoggerChannelTrait;.