Add Haskell, Cobol and Prolog

[Peristroff]

Please add Haskell, Cobol and Prolog languages. I know that some of these are legacy languages, but it would be cool to have them here (I have used Prolog in the past).

This is the cobol icon I could find: https://logowik.com/cobol-logo-vector-71110.html
Prolog icon is an owl: https://iconduck.com/icons/102336/file-type-prolog
Haskell is more popular but here's the icon anyways: https://seekvectors.com/post/haskell-icon

Great project and thank you!