Parse provided json to get configuration
    Empty default json:
    {
      "testfiles": [],
      "breakfailed": true,
      "onlyfailed": false,
      "verb": 3,
      "dump": 0,
      "crc": true,
      "scapy": "scapy",
      "preexec": {},
      "global_preexec": "",
      "outputfile": null,
      "local": true,
      "format": "ansi",
      "num": null,
      "modules": [],
      "kw_ok": [],
      "kw_ko": []
    }

def parse_config_file(config_path, verb=3):
    """Parse provided json to get configuration
    Empty default json:
    {
      "testfiles": [],
      "breakfailed": true,
      "onlyfailed": false,
      "verb": 3,
      "dump": 0,
      "crc": true,
      "scapy": "scapy",
      "preexec": {},
      "global_preexec": "",
      "outputfile": null,
      "local": true,
      "format": "ansi",
      "num": null,
      "modules": [],
      "kw_ok": [],
      "kw_ko": []
    }

    """
    import json
    import unicodedata
    with open(config_path) as config_file:
        data = json.load(config_file, encoding="utf8")
        if verb > 2:
            print("### Loaded config file", config_path, file=sys.stderr)

    def get_if_exist(key, default):
        return data[key] if key in data else default
    return Bunch(testfiles=get_if_exist("testfiles", []),
                 breakfailed=get_if_exist("breakfailed", True),
                 remove_testfiles=get_if_exist("remove_testfiles", []),
                 onlyfailed=get_if_exist("onlyfailed", False),
                 verb=get_if_exist("verb", 3),
                 dump=get_if_exist("dump", 0), crc=get_if_exist("crc", 1),
                 scapy=get_if_exist("scapy", "scapy"),
                 preexec=get_if_exist("preexec", {}),
                 global_preexec=get_if_exist("global_preexec", ""),
                 outfile=get_if_exist("outputfile", sys.stdout),
                 local=get_if_exist("local", False),
                 num=get_if_exist("num", None),
                 modules=get_if_exist("modules", []),
                 kw_ok=get_if_exist("kw_ok", []),
                 kw_ko=get_if_exist("kw_ko", []),
                 format=get_if_exist("format", "ansi"))