check for unused includes in C++

[mikaelarguedas]

It seems that cpplint's include_what_you_use doesn't check for unused included headers.
It would be great to either extend it or use another static analysis tool to check this

[wjwwood]

I think you'd either need https://github.com/include-what-you-use/include-what-you-use or Google's cppclean https://github.com/myint/cppclean.

[mikaelarguedas]

Indeed these are the too options I was considering. Should have provided the links, thanks for doing it!