admc/wd — pull request #219 by geekdave (2013-11-08 22:56:38+00:00)
Title: Add `saveScreenshot` API which actually saves to the filesystem.

The `takeScreenshot` API just returns base64 encoded data of the screenshot.
This method is more user-friendly and actually saves the image to the filesystem.

Usage:

```js
browser
.elementById("login")
.click()
.saveScreenshot("Logged_In") // saves Logged_In.png to the filesystem
.elementById("logout" )
.click()
.saveScreenshot("Logged_Out"); // saves Logged_Out.png to the filesystem
```