Integrate perlio:

[ 10640]
Disable :win32 layer as default till I get it working

[ 10632]
Work-in-progress win32 layer semi-functional, checking
for UNIX breakage.

[ 10627]
Work in progress UNIX-side edit of win32 PerLIO layer

p4raw-link: @10640 on //depot/perlio: 2f8118af5e6ae8b76fdc332011717931c71acde6
p4raw-link: @10632 on //depot/perlio: 0c4128adc5f62cd332ae4fa5bc8999c95d611d36
p4raw-link: @10627 on //depot/perlio: a8c08ecdc5ffec9869657a967edfe7b74a713a27

p4raw-id: //depot/perl@10641

diff --cc MANIFEST
Simple merge