MIME type names are inconsistent across different systems, so only first
component is used. For example, `file` in Travis Ubuntu detects Python scripts
as `text/x-java`, in Gentoo these are `text/x-python`.
Travis Ubuntu also uses magic file format different from the one
sys-apps/file-5.22 from Gentoo has, making it impossible to fix the issue by
just copying the files from my system.