improve serial hotplug (#389)

* - disable device when error indecates that the problem is not solvable on reconnect
- introduce a preOpenDelay of 2 seconds (currently value is hardcoded)

* rs232:
- make preOpenDelay available via webui
- fix preOpenDelay
- add basic usb serial detection

* - revert 3819ae7
- fix schema files

* make json checks compat with utf8+bom

* make shutdown effect a bit more flexible

libsrc/leddevice/LedDeviceAdalight.cpp

@@ -6,6 +6,7 @@ LedDeviceAdalight::LedDeviceAdalight(const QJsonObject &deviceConfig)
 	, _ligthBerryAPA102Mode(false)
 {
 	_deviceReady = init(deviceConfig);
+	connect(this,SIGNAL(receivedData(QByteArray)),this,SLOT(receivedData(QByteArray)));
 }
 
 LedDevice* LedDeviceAdalight::construct(const QJsonObject &deviceConfig)
@@ -74,3 +75,7 @@ int LedDeviceAdalight::write(const std::vector<ColorRgb> & ledValues)
 	return writeBytes(_ledBuffer.size(), _ledBuffer.data());
 }
 
+void LedDeviceAdalight::receivedData(QByteArray data)
+{
+	Debug(_log, ">>received %d bytes data", data.size());
+}