Re: [9front] Date and time handling.

[ori@eigenstate.org]

> well done!
> 
> i tried to do this years ago whilst writing an ical parser - and gave up in horror.
> 
> -Steve
> 

I should probably be absolutely clear: the manpage is aspirational, not
documentational, though I think the hard parts are done or close.

One thing that will annoy me: Currently, you need to specify the timezone
as the filename, eg, "US_Eastern", rather than as the well known name,
eg, "EST". There are two reasons for this.

1) We have no way to map from a timezone to the name, other than 
   opening each timezone file and reading the first line.

2) The timezone name that we store in those files is wrong. We only
   have 3 characters for the timezone, so "Australia_Tasmania" becomes
   EST instead of AEST.

I can hard-code a mapping, but that kind of sucks. I'd like to parse
the IANA timezone database and generate files instead, either with a
separate 'tzmap' file, or with duplicates for the abbreviated zones
that we can open directly.