[virt-tools-list] [osinfo] Extract language information from Windows ISOs

[Christophe Fergeau]

Hey,

Windows ISOs volume IDs contains some kind of language code which we can use
to know what locale the installer is in. This is useful as for unattended
installation, you have to somehow guess the language you are going to install
into, and if the ISO doesn't support this language, the installer asks you
about what language you want to use.

This series adds support for that through a new <lang-regex> tag and a mapping
table to turn the volume id language code to a locale identifier. I've tested
this code against a bunch of Win8 and Win7 ISOs, and I've had a quick look at
other Windows ISOs volume IDs to make sure they are similar.

I've got 2 issues with these patches, one is that they add Windows-specific code to
osinfo-db.c, I'm not sure how to make that nicer. My second issue is that I'm not sure
how to integrate this into the test suite. I could go with a hardcoded list of
volume ids/expected locales, but maybe someone has better ideas?

Christophe