Inconsistent Filenames

[bogdan-barbu]

The conventional filename for a file like this would be CODE_OF_CONDUCT.md, which is what's present in this very repository. However, on the official Web site, there are two versions, both unconventional: code_of_conduct.md and CODE_OF_CONDUCT.MD. The former is available via a direct download link from the specification page and the latter is generated from the adoption form. If it's a simple thing to fix, it would be nice because it's just an extra annoying rename everyone has to go through.