Update translations from Transifex:

 - Chinese (simplified)
 - Czech
 - German
 - Galician
 - Malay
 - Portuguese (Brazil)
 - Russian
 - Slovak
 - Swedish
 - Vietnamese
Language menu: Ensure "Language" always appears in English in menu entry.

If "Language" doesn't appear in the translated string, "(Language)" will be appended automatically.
Language menu: Use submenus to group language names starting with the same character.
Update translations from Transifex:

 - Greek.