[Remind-Fans] Sorting in Calendar Mode

[Edward Shapard]

Hello!

I noticed to day that sorting (-g) doesn't seem to work on the advance 
warnings in calendar mode (-ca, -sa).

So I'll get something like:
Foo in 15 days' time
Bar in 2 days' time

However, items are sorted by priority in calendar mode.

Ideally, I'd like these upcoming events to be listed below the current 
day's events.

Is there a way to add the number of days before an advance item to its 
priority so that it affects how it's sorted? Something like:

REM 2023-08-13 PRIORITY [5000 + days_until_trigger] MSG Foo

This way, three days before an event, it would have priority 5003 and 
show up lower on the list; two days before, it would have priority 5002; 
etc.

Thanks!