- rfc822-parse-date stringprocedure
Takes RFC-822 type date string, and returns eight values:
year, month, day-of-month, hour, minutes, seconds, timezone, day-of-week.
Timezone is an offset from UT in minutes. Day-of-week is a day from sunday, and may be #f if that information is not available. Month is an integer between 1 and 12, inclusive. If the string is not parsable, all the elements are #f.