Role: return only a single Role object since role is unique

Signed-off-by: Pekka Helenius <fincer89@hotmail.com>

bookstore/src/main/java/com/fjordtek/bookstore/model/auth/RoleRepository.java

@@ -2,8 +2,6 @@
 
 package com.fjordtek.bookstore.model.auth;
 
-import java.util.List;
-
 import org.springframework.data.repository.CrudRepository;
 import org.springframework.data.rest.core.annotation.RepositoryRestResource;
 
@@ -23,6 +21,6 @@ import org.springframework.data.rest.core.annotation.RepositoryRestResource;
 		)
 public interface RoleRepository extends CrudRepository<Role, Long> {
 
-	List<Role> findByName(String string);
+	Role findByName(String string);
 
 }