add a search Listener

A listener which provides a simple mechanism to add a search to any
paginated index.

It can be utilized by adding the following to relevant controllers:

	/**
	 * Before Filter callback:
	 **/
		public function beforeFilter() {
			if (isset($this->request->query['q'])) {
				App::uses('SearchListener', 'Crud.Controller/Event');
				$this->getEventManager()->attach(new SearchListener());
			}
			parent::beforeFilter();
		}

Put in the app controller to be able to use in any controller
add search listener test
declare implemented events