keeps daily record of keybr speed

keybr_speed.js

var storage = [];
$g_speed.$on('DOMSubtreeModified', function(e) {
    alert(e);
    setTimeout(function(){
        var speed = parseInt($g_speed.innerText);
        var d = new Date();
        var dt = ['getFullYear', 'getMonth', 'getDay'].map(function(e){
            return d[e]();
        }).join('-');
        storage[dt] = storage[dt] || [];
        storage[dt].push(speed);
        console.log(speed, storage);
    });
});