Get the db version

def namedb_read_version(path):
    """
    Get the db version
    """
    con = sqlite3.connect( path, isolation_level=None, timeout=2**30 )
    con.row_factory = namedb_row_factory

    sql = 'SELECT version FROM db_version;'
    args = ()

    try:
        rowdata = namedb_query_execute(con, sql, args, abort=False)
        row = rowdata.fetchone()
        return row['version']
    except:
        # no version defined
        return '0.0.0.0'
    finally:
        con.close()