entityqueue 8.x-1.0-alpha2

Changes since 8.x-1.0-alpha1:

• Follow-up to issue #2634154: items_target_id in entity_subqueue__items should not be an int.
• #2634154: items_target_id in entity_subqueue__items should not be an int.
• #2645060: Newly added entity queues are not getting listed under relationship in views.
• #2645064: When adding new entity queue, if Handler value is not selected (though it's a mandatory field), it throws error
• #2620520: Recoverable fatal error: Object of class Drupal\Core\Link could not be converted to string in Drupal\Core\Database\Statement->execute()