* Pick the version and build number directly from the install[.wim|.esd] XML index.
This forces us to mount the ISO during scan, but it's the only way to get an accurate Build number...
* Also drop linking to version.dll (along with the whole version.dll delay-loading shenanigans).
* Some "unofficial" Windows ISOs use a custom boot.wim that only includes the Setup
image at index 1, rather than at index 2, after the PE image, for official ISOs.
* Also refactor to add a long needed vhd.h header.
* Also fix a MinGW warning.