Create Japanese documentation directory

See merge request !1128



Merged-by: Hossein Pursultani <hpursultani@gitlab.com>
Approved-by: Marcel Amirault <mamirault@gitlab.com>
Approved-by: Hossein Pursultani <hpursultani@gitlab.com>
Reviewed-by: Marcel Amirault <mamirault@gitlab.com>
Co-authored-by: Lauren Barker <lbarker@gitlab.com>