- Figure out what LOCAL-TIME-DESIGNATOR is supposed to do and
  implement it

- Figure out a sane and unambiguous way to support intervals
    The problem: years are not always 365 days, months may be 28-31 days,
    and days may not be 24 hours long.  That leaves doing all intervals
    in seconds, which sucks.

- Write a more flexible formatting function for times, perhaps something
  like strftime() except lispy

- PARSE-TIMESTRING works fine, but we need a more human-friendly parser that
  can handle stuff like "08/03/2006 1:54pm CST"

- Support for other notational systems than the Gregorian

- Ideally, local-time should have everything that the ruby Date class does,
  as well as the time functions in the venerable and honored clsql library.
  This may be a tall order.

- We should integrate local-time with http://common-lisp.net/project/cl-l10n/
  and drop time/timezone related functionality from cl-l10n.
