DATACMNS-754 - Fixed code sample in repositories reference documentation.

PersonRepository example now shows Person persisted instead of User instances.

Original pull request: #140.

src/main/asciidoc/repositories.adoc

@@ -107,14 +107,14 @@ Standard CRUD functionality repositories usually have queries on the underlying
 +
 [source, java]
 ----
-interface PersonRepository extends Repository<User, Long> { … }
+interface PersonRepository extends Repository<Person, Long> { … }
 ----
 
 . Declare query methods on the interface.
 +
 [source, java]
 ----
-interface PersonRepository extends Repository<User, Long> {
+interface PersonRepository extends Repository<Person, Long> {
   List<Person> findByLastname(String lastname);
 }
 ----