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/TemporaryFile.h

@@ -0,0 +1,84 @@
+//
+// TemporaryFile.h
+//
+// Library: Foundation
+// Package: Filesystem
+// Module:  TemporaryFile
+//
+// Definition of the TemporaryFile class.
+//
+// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
+// and Contributors.
+//
+// SPDX-License-Identifier:	BSL-1.0
+//
+
+
+#ifndef Foundation_TemporaryFile_INCLUDED
+#define Foundation_TemporaryFile_INCLUDED
+
+
+#include "Poco/Foundation.h"
+#include "Poco/File.h"
+
+
+namespace Poco {
+
+
+class Foundation_API TemporaryFile: public File
+	/// The TemporaryFile class helps with the handling
+	/// of temporary files.
+	/// A unique name for the temporary file is
+	/// automatically chosen and the file is placed
+	/// in the directory reserved for temporary
+	/// files (see Path::temp()).
+	/// Obtain the path by calling the path() method
+	/// (inherited from File).
+	///
+	/// The TemporaryFile class does not actually
+	/// create the file - this is up to the application.
+	/// The class does, however, delete the temporary
+	/// file - either in the destructor, or immediately
+	/// before the application terminates.
+{
+public:
+	TemporaryFile();
+		/// Creates the TemporaryFile.
+
+	TemporaryFile(const std::string& tempDir);
+		/// Creates the TemporaryFile using the given directory.
+
+	~TemporaryFile();
+		/// Destroys the TemporaryFile and
+		/// deletes the corresponding file on
+		/// disk unless keep() or keepUntilExit()
+		/// has been called.
+
+	void keep();
+		/// Disables automatic deletion of the file in
+		/// the destructor.
+
+	void keepUntilExit();
+		/// Disables automatic deletion of the file in
+		/// the destructor, but registers the file
+		/// for deletion at process termination.
+
+	static void registerForDeletion(const std::string& path);
+		/// Registers the given file for deletion
+		/// at process termination.
+
+	static std::string tempName(const std::string& tempDir = "");
+		/// Returns a unique path name for a temporary
+		/// file in the system's scratch directory (see Path::temp())
+		/// if tempDir is empty or in the directory specified in tempDir
+		/// otherwise.
+
+private:
+	bool _keep;
+};
+
+
+} // namespace Poco
+
+
+#endif // Foundation_TemporaryFile_INCLUDED