[XeTeX] xdvipdfmx code updated

[Jonathan Kew]

For those who like to live on the bleeding edge, there have been some  
updates to the xdvipdfmx code... if you get the latest from  
Subversion TRUNK and build it, you should get rid of those annoying  
font-related warning messages (which were really pointless), and  
hyperlinks will now work when using opentype/truetype fonts.

I haven't given it a new version number and done an updated "release"  
yet, as there are still various other things I'd like to tidy up, but  
people are welcome to grab the current code and try it out.

JK