Block comment by inserting (instead of changing) lines?

For example, the following line:

```
    x=x*2;
    return x;
```

After `gb` with this plugin, both lines are changed:

```
    /* x=x*2;
    return x; */
```

This is bad for tracking code with Git. It would be better to block comment by inserting lines and preserving existing lines, like this:

```
    /*
    x=x*2;
    return x;
    */
```
```