Allow the decimal radix character '.' to work, regardless of
what the current locale's radix character happens to be,
while still allowing locale specific entry of fractional
seconds (ie: if you're in locale where the radix character
is ',' you san use "sleep 2.5" or "sleep 2,5" and they
accomplish the same thing).
This avoids issues with the "sleep 0.05" in rc.subr which
generated usage messages when a locale that does not use
'.' as its radix character was in use.
Reported on netbsd-users by Dima Veselov, with the problem
diagnosed by Martin Husemann
While here, tighten the arg validity checking (3+4 is
no longer permitted as a synonym of 3) and allow 0.0
to mean the same thing as 0 rather than being an error.
Also, make the SIGINFO reports a little nicer (IMO).
The ATF tests for sleep all pass (not that that means a lot).
UnifiedSplitRaw
