migrate to async IO model

new PIIODevice::interrupt() virtual method
new PIWaitEvent private class
PIEthernet and PISerial basically tested on Windows and Linux

libs/cloud/picloudclient.cpp

@@ -45,10 +45,11 @@ PICloudClient::PICloudClient(const PIString & path, PIIODevice::DeviceMode mode)
 
 PICloudClient::~PICloudClient() {
 	//piCoutObj << "~PICloudClient()";
-	softStopThreadedRead();
+	//softStopThreadedRead();
 	//eth.close();
 	//if (is_connected) disconnected();
-	close();
+	//close();
+	stopAndWait();
 	//piCoutObj << "~PICloudClient() closed";
 	internalDisconnect();
 //	stop(false);
@@ -69,6 +70,11 @@ void PICloudClient::setKeepConnection(bool on) {
 }
 
 
+void PICloudClient::interrupt() {
+	eth.interrupt();
+}
+
+
 bool PICloudClient::openDevice() {
 	//piCoutObj << "open";// << path();
 	bool op = eth.connect(PIEthernet::Address::resolve(path()), false);