modify template structure

- add editorconfig & pug config
- add watch command
- update gitignore with local envs

.editorconfig

@@ -0,0 +1,9 @@
+root = true
+[*]
+tab_width = 4
+indent_size = 2
+indent_style = space
+insert_final_newline = true
+trim_trailing_whitespace = true
+charset = utf-8
+end_of_line = lf