remove unused files

.editorconfig

@@ -1,16 +0,0 @@
-# editorconfig.org
-root = true
-
-[*]
-indent_style = space
-indent_size = 2
-end_of_line = lf
-charset = utf-8
-trim_trailing_whitespace = true
-insert_final_newline = true
-
-[*.md]
-trim_trailing_whitespace = false
-
-[Makefile]
-indent_style = tab