misc: updated chosen module

## Ready State: (Yes)

This Pull Request updates the chosen module in the drush make file from 2.0-beta2 to 2.0-beta4. This changes the path from where it downloads the library in the chosen drush make file. 

## Requirements & Dependencies


## Deployment Instructions

* Merge code.
* Run chosen.make again to download the correct version of the chosen library
* Clear caches with `drush cache-clear all`

## Usage/Test Instructions

* Make sure the chosen library works on the defined elements. In my case it also prevented the Panels relationship dialog to render, so that might be worth testing as well.