Don't introduce empty lines

[mvdan]

In the README, we show the result:

func Crasher() {
        a := []int{1, 2, 3}
        println(a[10])
}

We actually produce:

func Crasher() {
        a := []int{1, 2, 3}

        println(a[10])
}

Figure out a way to remove stuff from the AST without introducing these extra empty lines.

[mvdan]

We've gotten way better at this, but some added lines remain.