ACTIONS
=======

 * "activate-settings"
   Description: opens a page for changing indicator-datetime's settings
   State: None
   Parameter: None

 * "activate-planner"
   Description: opens an appointment editor.
   State: None
   Parameter: int64, a time_t hinting which day/time to show in the planner,
                     or 0 for the current day

 * "activate-appointment"
   Description: opens an appointment editor to the specified appointment.
   State: None
   Parameter: string, an opaque uid to specify which appointment to use.
                      This uid comes from the menuitems' target values.

 * "set-location"
   Description: Set the current location. This will try to set the current
   timezone to the new location's timezone.
   State: None
   Parameter: a timezone id string followed by a space and location name.
              Example: "America/Chicago Oklahoma City"

 * "calendar"
    Description: set which month/day should be given focus in the indicator's
                 calendar. The planner will look for appointments from this
                 day to the end of the same month.
                 Client code implementing the calendar view should call this
                 when the user clicks on a new day, month, or year.
    State: a dictionary containing these key value/pairs:
          "appointment-days": an array of day-of-month ints. Used by the
                              calendar menuitem to mark appointment days.
          "calendar-day": int64, a time_t. Used by the calendar menuitem
                          to know which year/month should be visible
                          and which day should have the cursor.
          "show-week-numbers": if true, show week numbers in the calendar.
    Parameter: int64, a time_t specifying which year/month should be visible
                      and which day should have the cursor.


CUSTOM MENUITEMS
================

 * Calendar
   - x-canonical-type         s "com.canonical.indicator.calendar"

 * Alarm
   - label                    s short summary of the appointment
   - x-canonical-type         s "com.canonical.indicator.alarm"
   - x-canonical-time         x the date of the appointment
   - x-canonical-time-format  s strftime format string

 * Appointment
   - label                    s short summary of the appointment
   - x-canonical-type         s "com.canonical.indicator.appointment"
   - x-canonical-color        s color of the appt's type, to give a visual cue
   - x-canonical-time         x the date of the appointment
   - x-canonical-time-format  s strftime format string

 * Location
   - label                    s the location's name, eg "Oklahoma City"
   - x-canonical-type         s "com.canonical.indicator.location"
   - x-canonical-timezone     s timezone that the location is in
   - x-canonical-time-format  s strftime format string