bugfix: detecting system users while dispatching emails was broken

Signed-off-by: Stephan Richter <s.richter@srsoftware.de>

user/src/main/java/de/srsoftware/umbrella/user/UserModule.java

@@ -147,6 +147,13 @@ public class UserModule extends BaseHandler implements UserService {
 		return users.load(session);
 	}
 
+	public Optional<UmbrellaUser> load(EmailAddress email){
+		try {
+			return Optional.of(users.load(email));
+		} catch (UmbrellaException ignored){
+			return empty();
+		}
+	}
 
 	@Override
 	public UmbrellaUser loadUser(long userId) throws UmbrellaException {

user/src/main/java/de/srsoftware/umbrella/user/api/UserDb.java

@@ -10,6 +10,7 @@ import de.srsoftware.umbrella.user.model.DbUser;
 import de.srsoftware.umbrella.user.model.Password;
 import java.util.Collection;
 import java.util.Map;
+import java.util.Optional;
 
 public interface UserDb {
 

user/src/main/java/de/srsoftware/umbrella/user/sqlite/SqliteDB.java

@@ -397,7 +397,6 @@ CREATE TABLE IF NOT EXISTS {0} (
 		}
 		if (user == null) throw unauthorized(FAILED_TO_LOAD_OBJECT_BY_ID, OBJECT,t(Text.USER), ID,key);
 		return user;
-
 	}
 
 	@Override