New due-date box shorthands/optimization
Tonight ==> today
(ton ==> today)
noon = 12:00pm/1200 hrs
Time disambiguation (if a duedate string lacks an @, comma, or "at", see if it contains a string of 3-4 digits or 2 digit strings separated by a colon, or 2 digits followed by "am" or "pm", and see if the date would parse with the assumption of a leading @)
"in <number> <time unit>" (eg, in 20 minutes, in 6 hours, in 2 weeks, etc) should parse out correctly.