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/AbstractStrategy.h

@@ -0,0 +1,77 @@
+//
+// AbstractStrategy.h
+//
+// Library: Foundation
+// Package: Cache
+// Module:  AbstractCache
+//
+// Definition of the AbstractStrategy class.
+//
+// Copyright (c) 2006, Applied Informatics Software Engineering GmbH.
+// and Contributors.
+//
+// SPDX-License-Identifier:	BSL-1.0
+//
+
+
+#ifndef Foundation_AbstractStrategy_INCLUDED
+#define Foundation_AbstractStrategy_INCLUDED
+
+
+#include "Poco/KeyValueArgs.h"
+#include "Poco/ValidArgs.h"
+#include "Poco/EventArgs.h"
+#include <set>
+
+
+namespace Poco {
+
+
+template <class TKey, class TValue> 
+class AbstractStrategy
+	/// An AbstractStrategy is the interface for all strategies. 
+{
+public:
+	AbstractStrategy()
+	{
+	}
+
+	virtual ~AbstractStrategy()
+	{
+	}
+
+	virtual void onUpdate(const void* pSender, const KeyValueArgs <TKey, TValue>& args)
+		/// Updates an existing entry.
+	{
+		onRemove(pSender,args.key());
+		onAdd(pSender, args);
+	}
+	
+	virtual void onAdd(const void* pSender, const KeyValueArgs <TKey, TValue>& key) = 0;
+		/// Adds the key to the strategy.
+		/// If for the key already an entry exists, an exception will be thrown.
+
+	virtual void onRemove(const void* pSender, const TKey& key) = 0;
+		/// Removes an entry from the strategy. If the entry is not found
+		/// the remove is ignored.
+
+	virtual void onGet(const void* pSender, const TKey& key) = 0;
+		/// Informs the strategy that a read-access happens to an element.
+
+	virtual void onClear(const void* pSender, const EventArgs& args) = 0;
+		/// Removes all elements from the cache.
+
+	virtual void onIsValid(const void* pSender, ValidArgs<TKey>& key) = 0;
+		/// Used to query if a key is still valid (i.e. cached).
+
+	virtual void onReplace(const void* pSender, std::set<TKey>& elemsToRemove) = 0;
+		/// Used by the Strategy to indicate which elements should be removed from
+		/// the cache. Note that onReplace does not change the current list of keys.
+		/// The cache object is responsible to remove the elements.
+};
+
+
+} // namespace Poco
+
+
+#endif // Foundation_AbstractStrategy_INCLUDED