[Remind-Fans] Categorize OMIT

[Tim Chase]

> As I understand it, to assign an omit to a specific reminder, one
> can use the keyword or a push-pop-context.
> As it now so happens, I live in a complicated world where compromises
> in cultural development lead to different holidays affecting different
> sets of activities.
[snip]
> What I do not want to do is to put holiday 3 in three different push-pop-contexts.

While I'm not sure this is the best solution, it's what I've used
for similar.  I've got federal holidays, city holidays (my beloved
is a city employee), and school holidays in play, so I have files
for each, and one for their commonality

 # common_hol.rem
 OMIT Dec 25 MSG Christmas
 ...

 # federal_hol.rem
 include common.rem
 OMIT Feb 22 MSG President's Day
 ...

 # city_hol.rem
 include common.rem
 OMIT Jun 19 MSG Juneteenth
 ...

 # school_hol.rem
 include common.rem
 OMIT Sep 1 2022 MSG Teacher in-service day
 ...

then in my respective calendars, I can include them in PUSH/POP blocks

 # school.rem
 PUSH
  include school_hol.rem
  REM OMIT Sat Sun MSG School
 POP
 REM Jan 26 2023 MSG 100th day of school
 REM Feb 21 2023 MSG Mystery reader

I made the school one reusable originally because our daughter's
preschool was on the same schedule as the local school-district,
but I wanted different calendar files for each.

I don't know if it's useful, but it works for me.

-tim