task/de04-ta02 -- Integrate the new POD hashing/archiving routine into
the Exporter

nparcel/b2cconfig.py
nparcel/conf/nparceld.conf
* new condition map options archive_ps_file and archive_png_file
* renamed the get_file_control() method to get_pod_control() and
  refactored the method to handle the archive_*_file condition map

nparcel/exporterdaemon.py
* replace reference to get_file_control() with get_pod_control()

nparcel/exporter.py
* factored out the the move_signature_file() method into the process()
  method
* new method archive_signature_file() that attempts to archive POD
  signature files
* updated the process() method to attempt POD file archiving and staging
task/de04-ta03 -- POD signature migrator tool

nparcel/bin/nppodmigrate
* new script to migrate old-style POD signature archives

nparcel/utils/files.py
* move_file() function now supports a dry run