integrate 5.8-maint: changes #18174 18187 18189-92 18202 18209 18214-5

integrate 5.8-maint: changes #18174 18187 18189-92 18202 18209 18214-5
p4raw-link: @18189 on //depot/maint-5.8/perl: 27314835b1b1ea8730d4a0eb871861ac238c63f9
p4raw-link: @18187 on //depot/maint-5.8/perl: 94e81ce4c47784f86829e70129b1d0a3e95ca51c
p4raw-link: @18174 on //depot/maint-5.8/perl: f8d24d869503bcd9df0e86aa5898c89996220bf8

p4raw-id: //depot/perl@18221
p4raw-branched: from //depot/maint-5.8/perl@18220 'branch in'
	ext/POSIX/t/is.t
p4raw-integrated: from //depot/maint-5.8/perl@18220 'copy in'
	README.os2 ext/GDBM_File/GDBM_File.pm ext/GDBM_File/Makefile.PL
	lib/Unicode/UCD.pm t/op/subst.t (@17645..) INSTALL t/op/grep.t
	(@18080..) ext/Fcntl/t/syslfs.t t/op/lfs.t (@18133..) 'merge
	in' t/op/eval.t (@17645..) pod/perldiag.pod (@18146..)
	lib/Unicode/UCD.t (@18156..) MANIFEST (@18173..)