Major plugin refactor and cleanup.

Switched to POCO library for unified platform/library interface.
Deprecated the external module API. It was creating more problems than solving.
Removed most built-in libraries in favor of system libraries for easier maintenance.
Cleaned and secured code with help from static analyzers.

vendor/POCO/Foundation/include/Poco/StreamChannel.h

@@ -0,0 +1,61 @@
+//
+// StreamChannel.h
+//
+// Library: Foundation
+// Package: Logging
+// Module:  StreamChannel
+//
+// Definition of the StreamChannel class.
+//
+// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
+// and Contributors.
+//
+// SPDX-License-Identifier:	BSL-1.0
+//
+
+
+#ifndef Foundation_StreamChannel_INCLUDED
+#define Foundation_StreamChannel_INCLUDED
+
+
+#include "Poco/Foundation.h"
+#include "Poco/Channel.h"
+#include "Poco/Mutex.h"
+#include <ostream>
+
+
+namespace Poco {
+
+
+class Foundation_API StreamChannel: public Channel
+	/// A channel that writes to an ostream.
+	///
+	/// Only the message's text is written, followed
+	/// by a newline.
+	///
+	/// Chain this channel to a FormattingChannel with an
+	/// appropriate Formatter to control what is contained 
+	/// in the text.
+{
+public:
+	using Ptr = AutoPtr<StreamChannel>;
+
+	StreamChannel(std::ostream& str);
+		/// Creates the channel.
+
+	void log(const Message& msg);
+		/// Logs the given message to the channel's stream.
+		
+protected:
+	virtual ~StreamChannel();
+
+private:
+	std::ostream& _str;
+	FastMutex     _mutex;
+};
+
+
+} // namespace Poco
+
+
+#endif // Foundation_StreamChannel_INCLUDED