db operations test and bug fix

[straceX]

• sqllitedb(const std::string &dbname);
• sqllitedb(const sqllitedb &sqllitedbObj);
• sqllitedb &operator=(const sqllitedb &sqllitedbObj);
• std::string db_version();
• bool sqllitedb::table_row_count(std::string table_name,int &row_count);
• bool sqllitedb::db_table_list();
• bool exec_querry(std::string querry);
• bool create_table(std::string querry);
• bool update_table(std::string querry);
• bool delete_table(std::string querry);