conver.js

var data = [
    {
        "timestamp": 1436450162,
        "temperature": 23
    }
];

var mgData = data.map(function (point) {
    return {
        date: new Date(point.timestamp * 1000),
        value: point.temperature
    }
});

MG.data_graphic({
    title: "Temperature",
    data: mgData /*, etc */
});