Integrate perlio:

[ 15412]
Check for sanity of UTF-8 keys in hashes
(feel free to add more tests...)

[ 15410]
Fix [ID 20020318.003] cannot open STDOUT into in memory variable
- when (e.g.) STDOUT is char special file and gets IoOFP
created - do _NOT_ pass num_svs as that fopen-s stringified
glob, and not fdopen-s the fd.
p4raw-link: @15412 on //depot/perlio: cb0a5b5c946748a0ce5472032178d97c33e21b33
p4raw-link: @15410 on //depot/perlio: dd37d22f759197ae537bfc89e7f0cd73321b19b3

p4raw-id: //depot/perl@15413