Integrate perlio:

[ 13950]
Win32 hides some errno-oid constants in <winsock.h> under assumed names.
This gets them into Errno.pm - yet to prove they end up in $!.

[ 13948]
remove embed.pl duplicates

[ 13944]
"Port" Devel::PPPort to Win32:
- need to set @INC before use in the test
- {} are special to dmake, so use ppport.h.PL
rather than commandline

p4raw-link: @13950 on //depot/perlio: 4d70086c95dd7d504d588db11daab964a36e98ee
p4raw-link: @13948 on //depot/perlio: bcd4838a2aabb71350585eb4c5a0be33ada1227d
p4raw-link: @13944 on //depot/perlio: a06d4b7fa7822309a686f69b7ef2469437e518ec

p4raw-id: //depot/perl@13958