Samiur Khan

Results 2 issues of Samiur Khan

`comm` is a part of the family of comparison tools but a reference page can help clarify the differences between `diff`, `cmp`, `comm`. suggested by ppannuto in #343

good for student

Tested by opening examples/ and core/. As the language is flushed out more, we can add more but deriving from cc-mode works for now. Also adds elisp to license pre-commit...

infrastructure
utilities