Revision history for plockf.

0.04	2017-03-19
	- cleanup only if lock file was successfully acquired
	- make sure O_RDONLY is everywhere specified
	- require newer Time::HiRes (because of RT #35899)
	- simplify acquire_lock_other if -k was given
	- fix minor Pod typo

0.03	2016-07-03
	- fix alarm handling

0.02	2016-07-03
	- implementation overhaul

0.01    2016-07-03
	- initial release