Incompatible changes:
* suffix `m` is no longer accepted as a synonym for `mo`
with date-only input, issue #76
Bugfixes:
* expose BSD routines (fgetln()) to yuck
* for dates passed to dateround(1) that coincidentally
match the roundspecs do read them as dates
* wrong timestamps read via -i %s signal error
* facilitate bmake build
* time rounding on date-only input keeps the date unchanged
* dateseq's short-cut iterator (2 date arguments) does not
interfere with the 3-argument version
* adding 0 date or time units does not change the summand
* datezone on times (without date) will return times
* zones are singletons now, opened and closed only once
OBS-URL: https://build.opensuse.org/package/show/utilities/dateutils?expand=0&rev=59
