adding date/time calculations to glib

[Jon Trowbridge <trow emccta com>]

I would like to propose that code for doing date and time calculations
be added to glib.
     
This is one area where it seems like all sorts of different free
programs are constantly reinventing the wheel.  For example, gncal and
gnumeric are both using different pieces of code to do basic
calculations like the number of days in a month, mapping mm/dd/yyyy
dates to julian dates, extracting dates from strings, calculating days
of the week, etc.
     
I'm now in a position where a few different free software projects
(guppi, gtk--plot and goose) that I'm working on are also going to
need to do date calculations.  Rather than just cutting and pasting
the same old code into these projects, I think that we would all be
best served if some common code to provide this functionality was set
up.
     
To this end, I'm volunteering to do the work necessary to add this
code to glib.  I'd probably use timeutil.{c,h} from gncal as the basis
for it, but with improvements and changes to fit it into glib's naming 
and coding conventions.  gncal and gnumeric (as well as any other
existing code that deals with dates and times) would hopefully be
switched over to using the new glib code, but this wouldn't have to
happen right away.
    
-JT