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/FileStream_WIN32.h

@@ -0,0 +1,71 @@
+//
+// FileStream_WIN32.h
+//
+// Library: Foundation
+// Package: Streams
+// Module:  FileStream
+//
+// Definition of the FileStreamBuf, FileInputStream and FileOutputStream classes.
+//
+// Copyright (c) 2007, Applied Informatics Software Engineering GmbH.
+// and Contributors.
+//
+// SPDX-License-Identifier:	BSL-1.0
+//
+
+
+#ifndef Foundation_FileStream_WIN32_INCLUDED
+#define Foundation_FileStream_WIN32_INCLUDED
+
+
+#include "Poco/Foundation.h"
+#include "Poco/BufferedBidirectionalStreamBuf.h"
+#include "Poco/UnWindows.h"
+
+
+namespace Poco {
+
+
+class Foundation_API FileStreamBuf: public BufferedBidirectionalStreamBuf
+	/// This stream buffer handles Fileio
+{
+public:
+	FileStreamBuf();
+		/// Creates a FileStreamBuf.
+
+	~FileStreamBuf();
+		/// Destroys the FileStream.
+
+	void open(const std::string& path, std::ios::openmode mode);
+		/// Opens the given file in the given mode.
+
+	bool close();
+		/// Closes the File stream buffer. Returns true if successful,
+		/// false otherwise.
+
+	std::streampos seekoff(std::streamoff off, std::ios::seekdir dir, std::ios::openmode mode = std::ios::in | std::ios::out);
+		/// change position by offset, according to way and mode
+
+	std::streampos seekpos(std::streampos pos, std::ios::openmode mode = std::ios::in | std::ios::out);
+		/// change to specified position, according to mode
+
+protected:
+	enum
+	{
+		BUFFER_SIZE = 4096
+	};
+
+	int readFromDevice(char* buffer, std::streamsize length);
+	int writeToDevice(const char* buffer, std::streamsize length);
+
+private:
+	std::string _path;
+	HANDLE _handle;
+	UInt64 _pos;
+};
+
+
+} // namespace Poco
+
+
+#endif // Foundation_FileStream_WIN32_INCLUDED