DATAREST-213 - Make sure legacy representation can be activated.

Altered the order of HttpMessageConvertersRegistered based on the default media type being defined. This causes the legacy representation to be rendered as default representation if the default media type on RepositoryRestConfiguration is set to something different from HAL.
DATAREST-203 - Fixed accidentally broken RepositorySearchController.

Due to the change in the default media type, the RepositorySearchController was totally broken as it used "produces" clauses in the request mapping. I've removed them and added test cases to make sure the search resources are exposed and are accessible.