close method
void
close()
Implementation
void close() {
if (_isClosed) return;
final functions = LMDBFunctions();
ErrorHandler(functions.mdbEnvSync(_mdbEnv, 1));
LMDBFunctions().mdbEnvClose(_mdbEnv);
_boxes.remove(_path);
_isClosed = true;
print("box at $_path is closed.");
}