task/ta-npe-mapper-11 -- make nparcel.LoaderDaemon._start()
T1250 EOF-aware

nparcel/loaderdaemon.py
* factor out the check_eof_flag() method into nparcel/utils/files.py

nparcel/mapperdaemon.py
* updated the _start() method to check for the T1250 EOF token

nparcel/utils/files.py
* new function check_eof_flag() which checks if given file is a
standard T1250 file by verifying if the last line contains
the string "%%EOF"