add eslint and editorconfig

.editorconfig

@@ -0,0 +1,15 @@
+; EditorConfig file: http://EditorConfig.org
+; Install the "EditorConfig" plugin into Sublime Text to use
+
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+insert_final_newline = true
+indent_style = space
+indent_size = 4
+trim_trailing_whitespace = true
+
+[package.json]
+indent_size = 2