Feature: adding Chosen to Events fields where applicable

This PR configures Location and Registration-type fields in Events to leverage the Chosen Module.
Chosen uses the Chosen jQuery plugin to make your <select> elements more user-friendly.

https://imagex.atlassian.net/browse/PUA-14

## Ready State: Yes

## Requirements & Dependencies

* Chosen

## Deployment Instructions

* Merge code.

## Usage/Test Instructions

* Ensure Event fields for Location and Registration include the chosen functionality.
* Visually view the changes on the homepage.