First tentative version.
Intermediate version ... still not working.
Got the due date from milestone.

Only missing stuff is related to new traceback from previous commit message.
Fixed "not iterable" exeception.

But for some reason date format still not valid for datetime
fields, getting:

Warning:
The ticket field 'userfinish' is invalid: Field userfinish does
not seem to look like a date. The correct format is YYYY-MM-DD.
The ticket field 'userstart' is invalid: Field userstart does not
seem to look like a date. The correct format is YYYY-MM-DD.
Merge remote branch 'upstream/master'