Adds an extractor class which enables us to extract filters from the parameter filter
stored inside a Service class instance.
Rewrote PrintingJobConfigurationManager to use the AbstractManager.

This reduces code duplication and let us use the integrated filtering
meachanism.
Enable filtering in Printing Window to show only valid configurations for this printing job.
Fixes an error in Frontend while creating a new Printing configuration.

The store is only loaded, if a newValue contains something. Otherwise
we would receive an exception from our service.