BibHarvest: PoS harvest changes

* Make "append" records contain the full MARCXML output from PoS.

* Introduce CFG_POS_DEBUG variable to enable DEBUG mode which
  do not submit records to FTP.

Reported-by: Kirsten Sachs <kirsten.sachs@desy.de>
Signed-off-by: Jan Aage Lavik <jan.age.lavik@cern.ch>
BibCatalog: adjust checks to expect ticket ID as string

Signed-off-by: Jan Aage Lavik <jan.age.lavik@cern.ch>