StreamDock 基类

所有具体型号设备的控制类都需要继承StreamDock基类，StreamDock基类提供了以下方法：

获取设备的固件版本

unsigned char *streamDock::getFirmVersion(int lenth)

int streamDock::open()

int streamDock::disconnected()

int streamDock::setBrightness(int percent)

 int streamDock::setBackgroundImg(std::string path)

unsigned char * streamDock::read()

int streamDock::setKeyImg(std::string path,int key)

int streamDock::cleaerIcon(int index)

int streamDock::clearAllIcon()

int streamDock::wakeScreen()

int streamDock::refresh()