Integrate perlio:

[  8117]
Win32 tweaks to get Encode to build
- temp hack to makedef.pl till PerlIO is properly "exported".
- MSVC dislikes
static encpage_t foo[];
so make 'em extern for now.

[  8116]
Document the new files

p4raw-link: @8117 on //depot/perlio: 18b7339f76ca9f2454845b454e0d2168c487e8ee
p4raw-link: @8116 on //depot/perlio: 9a5ca08e7f5b67208359eefb1f4b7db6c2880dcb

p4raw-id: //depot/perl@8118

diff --cc MANIFEST
Simple merge