Fixed syntax error
Prepared field for job files
Added debug option to keep the jobber in the foreground
Feature for BookBuilder: cover images
Fixed tests
Create a zip file with all the files used in the bookbuilder
Offer the sources as download for BB
Revert "Prepared field for job files"

This reverts commit af00f964a8c346926a58275b67aa8bd625d17459.

Not needed
Merge branch 'bbfiles'