Add GameType Entity, Service and Repository. Test add GameType done.

src/main/java/fr/eni/demo/dal/GameTypeRepository.java

@@ -0,0 +1,9 @@
+package fr.eni.demo.dal;
+
+import fr.eni.demo.bo.GameType;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface GameTypeRepository extends JpaRepository<GameType, Long> {
+}