Syntax Issue In Readme

[hankbrigham]

In the readMe, this code is missing a brace after onEventClick.

    month={7}
    year={2015}
    events={events} 
    onEventClick={(target, eventData, day) => console.log(eventData) 
    />```

Here is the fix.

```<EventCalendar 
    month={7}
    year={2015}
    events={events} 
    onEventClick={(target, eventData, day) => console.log(eventData)}
    />```

Also you could add this to the readMe.

To update import for ES6, use:

`import EventCalendar from 'react-event-calendar';`