Add grain to _parse_basic_info() about python-duckling

[FraBle]

Pull requests are always welcome :)

[cmuell89]

Pulled down. Running tests.

[FraBle]

I integrated grain now into the wrapper as well. It will return something like

    {
        "dim": "time",
        "end": 23,
        "start": 6,
        "text": "for 2 hours today",
        "value": {
            "grain": "minute",
            "others": [
                {
                    "grain": "minute",
                    "value": "2017-05-09T16:56:00.000-07:00"
                }
            ],
            "value": "2017-05-09T16:56:00.000-07:00"
        }
    }

Released with version 1.6.0