Integrate from the maint-5.8/ branch :

Integrate from the maint-5.8/ branch :
changes 18219, 18236, 18242-3, 18247-8,
18253-5, 18257, 18273-6

p4raw-id: //depot/perl@18280
p4raw-branched: from //depot/maint-5.8/perl@18279 'branch in'
	t/op/lc_user.t
p4raw-integrated: from //depot/maint-5.8/perl@18279 'copy in'
	lib/File/Copy.pm (@17645..) lib/utf8_heavy.pl pod/perlsec.pod
	(@18080..) hints/irix_6.sh (@18173..) t/uni/tr_utf8.t
	(@18197..) pod/perlunicode.pod (@18242..) t/op/pat.t (@18248..)
	t/op/split.t (@18274..) 'edit in' pod/perlguts.pod (@18242..)
	'merge in' pp.c (@18126..) MANIFEST (@18234..)
p4raw-integrated: from //depot/maint-5.8/perl@18254 'merge in'
	pod/perldiag.pod (@18234..)