Rubykuby/containing_backend — pull request #15 by Rubykuby (2014-11-20 12:28:51+00:00)
Title: Added abstract ContainerHolder, implemented it in Transporter and Agv

To avoid code duplication, I made a ContainerHolder class. This is extended in `Vehicle` (and therefore `Agv` and `Transporter`) and should in the future be extended in the `Storage` class.