Zipfulldata refactor

I refactored the Zipfulldata job.

* I split it up into several smaller methods to make their individual tasks more clear and to improve testability
* the job is being instantiated to reduce the variable mess
* more and better tests
* Each run creates a temporary directory with all the data to be zipped and deletes it afterwards. This way we don't have to delete all the temporary files separately.

Please, run the job and compare the outcome with the old version's outcome, to see if I have accidentally changed anything.