Missing commas in code example in the README

[sorrat]

Fixed:

new Alerter({
    title: "Like this alert?",  // or a svelte component instance
    style: "background: green; border-radius: 1px;",  // Optional.  You can also style alerts with this css selector: .svelte-alerter-component.alert
    time: 3000,  // Alert will disapear in 3 seconds.  If no value is specified, the alert will not disapear automaticly
    undo: () => {console.log("Undone!")},  // If a value is specified, an undo button will apear on the alert.  You can style this button with .svelte-alerter-component.undo
}, () => {
    console.log("Alert has been removed!");
})

[Vehmloewff]

Thanks!