<issue_start><issue_comment>Title: Add EditorConfig file
username_0: More info here: https://editorconfig.org

Also fix issues with newlines and trailing whitespaces.
<issue_comment>username_0: No, this stuff exactly for VCS. For single style between all contributors. If somebody will write a code (or documentation or something else) with trailing spaces, then somebody else will have enabled setting for deleting trailing spaces, yet another will indent with tabs, and fourth will use spaces for indentation… it's a mess. And this file, tool, is intended for unifying. If you don't want it and mixing spaces with tabs and unrelated changes of trailing spaces and newlines are OK for you — OK. But I still recommend this.
<issue_comment>username_0: One more time: if one user adds their config with tabs indentation, and another user adds with spaces indentation — it's OK as freedom but it's bad as single-project-style. You can ignore this file, but for users with EditorConfig support and for reviewers it'd be easier to write correct (suitable) code.