Fix wrong-import-order

src/mailcow/menu.py:9:0: C0411: standard import "import argparse" should be placed before "from mailcow.globals import CONF" (wrong-import-order)
src/mailcow/__init__.py:4:0: C0411: standard import "import json" should be placed before "import yaml" (wrong-import-order)
src/mailcow/__init__.py:5:0: C0411: third party import "import requests" should be placed before "import yaml" (wrong-import-order)