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/KeyValueArgs.h

@@ -0,0 +1,73 @@
+//
+// KeyValueArgs.h
+//
+// Library: Foundation
+// Package: Cache
+// Module:  KeyValueArgs
+//
+// Definition of the KeyValueArgs class.
+//
+// Copyright (c) 2006, Applied Informatics Software Engineering GmbH.
+// and Contributors.
+//
+// SPDX-License-Identifier:	BSL-1.0
+//
+
+
+#ifndef Foundation_KeyValueArgs_INCLUDED
+#define Foundation_KeyValueArgs_INCLUDED
+
+
+#include "Poco/Foundation.h"
+
+
+namespace Poco {
+
+
+template <class TKey, class TValue> 
+class KeyValueArgs
+	/// Simply event arguments class to transfer a key and a value via an event call.
+	/// Note that key and value are *NOT* copied, only references to them are stored.
+{
+public:
+	KeyValueArgs(const TKey& aKey, const TValue& aVal): 
+		_key(aKey), 
+		_value(aVal)
+	{
+	}
+
+	KeyValueArgs(const KeyValueArgs& args):
+		_key(args._key), 
+		_value(args._value)
+	{
+	}
+
+	~KeyValueArgs()
+	{
+	}
+
+	const TKey& key() const
+		/// Returns a reference to the key,
+	{
+		return _key;
+	}
+
+	const TValue& value() const
+		/// Returns a Reference to the value.
+	{
+		return _value;
+	}
+
+protected:
+	const TKey&   _key;
+	const TValue& _value;
+
+private:
+	KeyValueArgs& operator = (const KeyValueArgs& args);
+};
+
+
+} // namespace Poco
+
+
+#endif // Foundation_KeyValueArgs_INCLUDED