[xslt] Win32 testplugin target usage

[Rush Manbert <rush manbert com>]

Hello,

I have version of libxslt and I'm installing it in Windows. I wanted to 
run whatever tests there might be, so looked at the targets that are 
defined in Makefile.msvc. The only thing I find is "testplugin" and it 
is not at all clear to me what I can do with the DLL that it builds. 
Does anyone have any pointers for me?

Thanks,
Rush