task/ta-npi-017-15 -- sort report items based on JOB_KEY

nparcel/exporter.py
* new method get_header_column() which returns the index position of a
  given header token
* updated the report() method so that it sorts line items on JOB_KEY
task/ta-npi-017-13 -- ftp to pick up *.png files

nparcel/ftp.py
* updated the process() method to source *.png files in addition to
  *.ps files