userDao: Implement list()

database/userdaosqlite.h

@@ -13,6 +13,7 @@ class UserDaoSqlite : public UserDao, protected SqliteDao
 	std::optional<User> find(std::string username);
 	std::optional<User> find(int id);
 
+	std::vector<User> list(QueryOption o);
 	void deleteUser(std::string username);
 	void save(const User &u);
 	using SqliteDao::SqliteDao;