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/LRUCache.h

@@ -0,0 +1,56 @@
+//
+// LRUCache.h
+//
+// Library: Foundation
+// Package: Cache
+// Module:  LRUCache
+//
+// Definition of the LRUCache class.
+//
+// Copyright (c) 2006, Applied Informatics Software Engineering GmbH.
+// and Contributors.
+//
+// SPDX-License-Identifier:	BSL-1.0
+//
+
+
+#ifndef Foundation_LRUCache_INCLUDED
+#define Foundation_LRUCache_INCLUDED
+
+
+#include "Poco/AbstractCache.h"
+#include "Poco/LRUStrategy.h"
+
+
+namespace Poco {
+
+
+template <
+	class TKey, 
+	class TValue,
+	class TMutex = FastMutex, 
+	class TEventMutex = FastMutex
+> 
+class LRUCache: public AbstractCache<TKey, TValue, LRUStrategy<TKey, TValue>, TMutex, TEventMutex>
+	/// An LRUCache implements Least Recently Used caching. The default size for a cache is 1024 entries.
+{
+public:
+	LRUCache(std::size_t size = 1024):
+		AbstractCache<TKey, TValue, LRUStrategy<TKey, TValue>, TMutex, TEventMutex>(LRUStrategy<TKey, TValue>(size))
+	{
+	}
+
+	~LRUCache()
+	{
+	}
+
+private:
+	LRUCache(const LRUCache& aCache);
+	LRUCache& operator = (const LRUCache& aCache);
+};
+
+
+} // namespace Poco
+
+
+#endif // Foundation_LRUCache_INCLUDED