When attached to Redis Wallabag will allow users to import but never starts

[ViViDboarder]

This had to be done manually from the container. It should either be scheduled within the container or kicked off by the application after the import. If the later solution is desired, this could be moved to the web application project.

[janLo]

I think the worker should be started as a separate service (container). PR #45 provides basic support for that.