Streamline Python file headers somewhat

- Add coding statement
  - Import all modules in one line where possible
  - Order: __future__, typing, plain imports, from imports,
    janware modules

Signed-off-by: Jan Lindemann <jan@janware.com>

tools/python/jwutils/Cmd.py

@@ -1,17 +1,16 @@
+# -*- coding: utf-8 -*-
+
 from __future__ import annotations
 from typing import List, Type, Union, TypeVar
-import abc
-import argparse
-from abc import ABC
+import inspect, sys, re, abc, argparse
 from argparse import ArgumentParser, _SubParsersAction
-import inspect, sys, re
 
 from jwutils import log
 
 # full blown example of one level of nested subcommands
 # git -C project remote -v show -n myremote
 
-class Cmd(ABC): # export
+class Cmd(abc.ABC): # export
 
     @abc.abstractmethod
     async def run(self, args):