Cancel on prompt boxes

This is my first time editing a file, but i had the problem prompt boxes couldn't be cancelled (and also the other cancelable didn't really cancel) so i changed a few things as you can see... Hope i will help you!

Maybe i'm all wrong, don't know for sure..
Use two-space indentation not tabs.

Also `if` statements should look like this:

```javascript
if (happy) {
  dance();
}
```

Binary operators should be separated by space:

```javascript
var x = 1 + 10 / 5;
```