insertAfter adds empty line before

`insertAfter` adds new line before inserted ast.

I created second import by jscodeshift so in js it looks like
```
//Core
import React, { Component, PropTypes } from 'react';

import connect from 'react-redux';
```

But should be:
```
import React, { Component, PropTypes } from 'react';
import connect from 'react-redux';
```