Set track=True when calling sifting.read_candidates() so that all bad candidates are available when making sifting summary plots.
No longer need to exclude 'prepfold_sigma' rating when calling rate_pfds.py since prepfold_sigma is no longer a registered rater.
Changed imagemagick 'convert' command when making pngs to produce prettier plots on guillimin phase 2.
Updated 'lib/python/formats/accelcands.py' to be compatible with the output of the new PRESTO sifting.py
The output of list_files on the Cornell FTP server changed at some point, so fixed in CornellFTP.py.