D1 Mini Support on Windows

[davidboultbee]

vanguard/init.py needs the following extra model...

    "d1_mini": {
        "manufacturer": "20",
        "device": "4016",
        "flash_size": "4MB",
        "flash_mode":"qio",
    },

Also escaping of windows file paths (to firmware images) is fragile to spaces in the path.