Improve delete message.

Add unit test.

wise-webapp/src/main/java/com/wisemapping/dao/UserManager.java

@@ -45,6 +45,6 @@ public interface UserManager {
 
     public User createUser(User user, Collaborator col);
 
-    public void deleteUser(User user);
+    public void removeUser(@NotNull User user);
 
 }

wise-webapp/src/main/java/com/wisemapping/dao/UserManagerImpl.java

@@ -110,9 +110,8 @@ public class UserManagerImpl
     }
 
     @Override
-    public void deleteUser(@NotNull final User user) {
+    public void removeUser(@NotNull final User user) {
         getHibernateTemplate().delete(user);
-        getHibernateTemplate().flush();
     }
 
     public void auditLogin(@NotNull AccessAuditory accessAuditory) {