New file, taken from fileutils 4.0.27, with the
following changes: Use @sc where appropriate. Document the ranges of
supported times more precisely. Add Eggert to getdate authors.
Document old Latin 12m/12pm tradition. Remove list of alphabetic time
zone names, as it wasn't correct and people shouldn't be relying on it
anyway. Relative items also account for non-DST adjustments. Fix
some misspellings.