Add .editorconfig

Helps with formatting files cross IDE/editor.

How can we make sure this does not conflict with our .clang-format and .clang-tidy? Is there some way to validate the one against the other. Did you generate the .editorconfig from the .clang-format file and what is the benefit of having both?

I have to double check if they conflict. The benefit of editorconfig is that is gets taken into account by most IDEs and supports multiple file types. Since we already have clang-format which gets taken into account by Clion, a reduced version without JetBrains specific configuration might actually be enough.

closed