[XeTeX] Patch: Add an entry for stemv

[Michiel Kamermans]

<<Well, some users in China asked me to write a patch for xetex, so I 
did so.. However, I agree with you that we should not do this in engine 
level. (and I think there is no need to do this in driver level either, 
since users can edit and fine tuning their fonts using any advanced font 
editing software.)>>

Except that for commercial fonts (like those supplied 'for free' with 
microsoft of adobe products) doing so would be illegal...
Adding it in at the driver level sounds like a pretty good idea 
(provided someone makes mention of this functionality in an obvious place =)

- Mike "Pomax" Kamermans
www.nihongoresources.com