add .editorconfig file at the top level of the project

.editorconfig

@@ -0,0 +1,15 @@
+# top-most EditorConfig file
+root = true
+
+# Unix-style newlines with a newline ending every file
+[*]
+charset = utf-8
+end_of_line = lf
+insert_final_newline = true
+
+# Matches multiple files with brace expansion notation
+[*.v]
+indent_style = tab
+
+[Makefile]
+indent_style = tab