Merge branch 'develop-v9' into 'master'

Classes/Command/NotificationCommand.php

Classes/Command/TestNotificationCommand.php

Classes/Controller/RoomController.php

Classes/Controller/SessionController.php

Classes/Controller/SlotController.php

Classes/Service/DeviceSessionService.php

Classes/ViewHelpers/IsPastViewHelper.php

Configuration/Commands.php

Configuration/TCA/tx_t3cssessions_domain_model_device.php

Configuration/TCA/tx_t3cssessions_domain_model_room.php

Configuration/TCA/tx_t3cssessions_domain_model_session.php

Configuration/TCA/tx_t3cssessions_domain_model_slot.php

Resources/Private/Language/locallang_db.xlf

composer.json

ext_localconf.php