Add support for Windows systems using non-English languages

[zhouraym]

Previously, the code relied on language-specific
output from powercfg -q to extract the GUIDs
for the current power scheme, display subgroup,
and brightness setting. This approach failed on
Windows systems using non-English languages
due to localized descriptions (e.g.,(Display) or
(Display brightness) not matching).

[zhouraym]

I have fixed this in PR https://github.com/Jabbath/node-brightness/pull/3