task/us89-ta34 -- Exporter can extract connote and item number from
inbound ParcelPoint report files

nparcel/exporter.py
* new method parse_report_file() that can parse the contents of a
  report file and extract the connote and item number fields
* new attribute connote_header that is a token used to identify the
  connote column in the Exporter report file
* new attribute item_nbr_header token used to identify the item number
  column in the Exporter report file

nparcel/b2cconfig.py
nparcel/conf/nparceld.conf
* support for the new attributes connote_header and item_nbr_header

nparcel/exporterdaemon.py
* refactored the _start() method to construct a kwargs dictionary in
  preparation for a varags-based initialisation of an Exporter() object