add EditorConfig dotfile

.editorconfig

@@ -0,0 +1,23 @@
+# Editor config from Quickstart
+# qkst.io/dotfiles/editorconfig
+
+root = true
+
+[*]
+end_of_line = lf
+insert_final_newline = true
+
+[*.md]
+trim_trailing_whitespace = false
+
+[*.js]
+indent_style = space
+indent_size = 2
+
+[Makefile]
+indent_style = tab
+indent_size = 8
+
+[*.{js}]
+charset = utf-8
+trim_trailing_whitespace = true