'0' was being cast as Boolean True - need to convert to integer to evaluate as False
Postgresql doesn't like ints where bools are expected. Convert to bool by first converting to integer (bool('0') was evaluating as True)
Allow Unicode in key fields
Improve unicode parsing. From https://github.com/bmander/gtfs/commit/e0390740ef951bebc2e1a5448abc68e51891833d
Remove unicode BOM if present
Deal correctly with BOM in Zip and plain text files