Relative to absolute url in README



![](https://cloud.githubusercontent.com/assets/3849459/3485732/b6c2d4a0-03fa-11e4-9338-65567f17ee9a.png)
Should fix issue #33, although the regex is sketch.
Open to suggestions to improve this (Y)
Prefer line-breaking like this:

```js
this.replaceRelativeToAbsoluteImage(
    html, this.props.githubRepoUrl);
```