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/XML/include/Poco/DOM/DOMImplementation.h

@@ -0,0 +1,82 @@
+//
+// DOMImplementation.h
+//
+// Library: XML
+// Package: DOM
+// Module:  DOM
+//
+// Definition of the DOM DOMImplementation class.
+//
+// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
+// and Contributors.
+//
+// SPDX-License-Identifier:	BSL-1.0
+//
+
+
+#ifndef DOM_DOMImplementation_INCLUDED
+#define DOM_DOMImplementation_INCLUDED
+
+
+#include "Poco/XML/XML.h"
+#include "Poco/XML/XMLString.h"
+
+
+namespace Poco {
+namespace XML {
+
+
+class DocumentType;
+class Document;
+class NamePool;
+
+
+class XML_API DOMImplementation
+	/// The DOMImplementation interface provides a number of methods for
+	/// performing operations that are independent of any particular instance
+	/// of the document object model.
+	/// In this implementation, DOMImplementation is implemented as a singleton.
+{
+public:
+	DOMImplementation();
+		/// Creates the DOMImplementation.
+		
+	~DOMImplementation();
+		/// Destroys the DOMImplementation.
+
+	bool hasFeature(const XMLString& feature, const XMLString& version) const;
+		/// Tests if the DOM implementation implements a specific feature.
+		///
+		/// The only supported features are "XML", version "1.0" and "Core", 
+		/// "Events", "MutationEvents" and "Traversal", version "2.0".
+	
+	// DOM Level 2
+	DocumentType* createDocumentType(const XMLString& name, const XMLString& publicId, const XMLString& systemId) const;
+		/// Creates an empty DocumentType node. Entity declarations and notations 
+		/// are not made available. Entity reference expansions and default attribute 
+		/// additions do not occur.
+
+	Document* createDocument(const XMLString& namespaceURI, const XMLString& qualifiedName, DocumentType* doctype) const;
+		/// Creates an XML Document object of the specified type with its document element.
+		///
+		/// Note: You can also create a Document directly using the new operator.
+
+	static const DOMImplementation& instance();
+		/// Returns a reference to the default DOMImplementation
+		/// object.
+		
+private:
+	static const XMLString FEATURE_XML;
+	static const XMLString FEATURE_CORE;
+	static const XMLString FEATURE_EVENTS;
+	static const XMLString FEATURE_MUTATIONEVENTS;
+	static const XMLString FEATURE_TRAVERSAL;
+	static const XMLString VERSION_1_0;
+	static const XMLString VERSION_2_0;	
+};
+
+
+} } // namespace Poco::XML
+
+
+#endif // DOM_DOMImplementation_INCLUDED