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/StrategyCollection.h

@@ -0,0 +1,133 @@
+//
+// StrategyCollection.h
+//
+// Library: Foundation
+// Package: Cache
+// Module:  StrategyCollection
+//
+// Definition of the StrategyCollection class.
+//
+// Copyright (c) 2006, Applied Informatics Software Engineering GmbH.
+// and Contributors.
+//
+// SPDX-License-Identifier:	BSL-1.0
+//
+
+
+#ifndef Foundation_StrategyCollection_INCLUDED
+#define Foundation_StrategyCollection_INCLUDED
+
+
+#include "Poco/KeyValueArgs.h"
+#include "Poco/ValidArgs.h"
+#include "Poco/AbstractStrategy.h"
+#include "Poco/SharedPtr.h"
+#include <vector>
+
+
+namespace Poco {
+
+
+template <class TKey, class TValue> 
+class StrategyCollection: public AbstractStrategy<TKey, TValue>
+	/// An StrategyCollection is a decorator masking n collections as a single one.
+{
+public:
+	using Strategies = std::vector<SharedPtr<AbstractStrategy<TKey, TValue>>>;
+	using Iterator = typename Strategies::iterator;
+	using ConstIterator = typename Strategies::const_iterator;
+
+public:
+	StrategyCollection()
+	{
+	}
+
+	~StrategyCollection()
+	{
+	}
+
+	void pushBack(AbstractStrategy<TKey, TValue>* pStrat)
+		/// Adds an AbstractStrategy to the collection. Class takes ownership of pointer
+	{
+		_strategies.push_back(SharedPtr<AbstractStrategy<TKey, TValue>>(pStrat));
+	}
+
+	void popBack()
+		/// Removes the last added AbstractStrategy from the collection.
+	{
+		_strategies.pop_back();
+	}
+
+	void onAdd(const void* pSender, const KeyValueArgs <TKey, TValue>& key)
+		/// Adds the key to the strategy.
+		/// If for the key already an entry exists, it will be overwritten.
+	{
+		Iterator it = _strategies.begin();
+		Iterator endIt = _strategies.end();
+		for (; it != endIt; ++it)
+		{
+			(*it)->onAdd(pSender, key);
+		}
+	}
+
+	void onRemove(const void* pSender, const TKey& key)
+		/// Removes an entry from the strategy. If the entry is not found
+		/// the remove is ignored.
+	{
+		Iterator it = _strategies.begin();
+		Iterator endIt = _strategies.end();
+		for (; it != endIt; ++it)
+		{
+			(*it)->onRemove(pSender, key);
+		}
+	}
+
+	void onGet(const void* pSender, const TKey& key)
+	{
+		Iterator it = _strategies.begin();
+		Iterator endIt = _strategies.end();
+		for (; it != endIt; ++it)
+		{
+			(*it)->onGet(pSender, key);
+		}
+	}
+
+	void onClear(const void* pSender, const EventArgs& args)
+	{
+		Iterator it = _strategies.begin();
+		Iterator endIt = _strategies.end();
+		for (; it != endIt; ++it)
+		{
+			(*it)->onClear(pSender, args);
+		}
+	}
+
+	void onIsValid(const void* pSender, ValidArgs<TKey>& key)
+	{
+		Iterator it = _strategies.begin();
+		Iterator endIt = _strategies.end();
+		for (; it != endIt && key.isValid(); ++it)
+		{
+			(*it)->onIsValid(pSender, key);
+		}
+	}
+
+	void onReplace(const void* pSender, std::set<TKey>& elemsToRemove)
+	{
+		Iterator it = _strategies.begin();
+		Iterator endIt = _strategies.end();
+		for (; it != endIt; ++it)
+		{
+			(*it)->onReplace(pSender, elemsToRemove);
+		}
+	}
+
+protected:
+	Strategies _strategies;
+};
+
+
+} // namespace Poco
+
+
+#endif // Foundation_StrategyCollection_INCLUDED