task/ta-npi-016-19 -- support for conditional email

nparcel/loader.py
* deprecated the special email requirements
* update process() method so that connote is taken from the cleansed
  and validated job_item_data variable
* update process() method so that email comms are sent only if the
  facility is enabled

nparcel/emailer.py
* automated sender identification now performed in __init__
* refactored the send() method so that it incorporates email recipient
  validation

nparcel/loaderdaemon.py
* deprecated all reference to the POC special email facility