code: public String getAvailableServices() throws JsonGenerationException, JsonMappingException, IOException {
  		DescribeServices services = serviceManager.getAvailableServices();
  
  		return services.asJSON();
  	}
docs: Returns a JSON containing the describe service document of each service
  registered into the library
  
  @return
  @throws IOException
  @throws JsonMappingException
  @throws JsonGenerationException