active handling for cygwin

[Katsuhiro Kondou]

In article <83znv07sjv.fsf at ass-kicking.kicks-ass.org>,
	greg andruk <gja at meowing.net> wrote;

} Here's the torture needed to add/remove active lines under Windows.
} nnrpd already skips active lines that begin with ".\0", and I told
} storage/expire.c to do pretty much the same.  The dot-nul padding
} compensates for a teensy race.

Also applied.  Thanks.
-- 
Katsuhiro Kondou