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/SAX/DefaultHandler.h

@@ -0,0 +1,83 @@
+//
+// DefaultHandler.h
+//
+// Library: XML
+// Package: SAX
+// Module:  SAX
+//
+// SAX-2 DefaultHandler class.
+//
+// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
+// and Contributors.
+//
+// SPDX-License-Identifier:	BSL-1.0
+//
+
+
+#ifndef SAX_DefaultHandler_INCLUDED
+#define SAX_DefaultHandler_INCLUDED
+
+
+#include "Poco/XML/XML.h"
+#include "Poco/SAX/EntityResolver.h"
+#include "Poco/SAX/DTDHandler.h"
+#include "Poco/SAX/ContentHandler.h"
+#include "Poco/SAX/ErrorHandler.h"
+
+
+namespace Poco {
+namespace XML {
+
+
+class XML_API DefaultHandler: public EntityResolver, public DTDHandler, public ContentHandler, public ErrorHandler
+	/// Default base class for SAX2 event handlers. 
+	/// This class is available as a convenience base class for SAX2 applications: 
+	/// it provides default implementations for all of the
+	/// callbacks in the four core SAX2 handler classes:
+	///      * EntityResolver 
+	///      * DTDHandler 
+	///      * ContentHandler 
+	///      * ErrorHandler 
+	/// Application writers can extend this class when they need to implement only 
+	/// part of an interface; parser writers can instantiate this
+	/// class to provide default handlers when the application has not supplied its own.
+{
+public:
+	DefaultHandler();
+		/// Creates the DefaultHandler.
+		
+	~DefaultHandler();
+		/// Destroys the DefaultHandler.
+	
+	// EntityResolver
+	InputSource* resolveEntity(const XMLString* publicId, const XMLString& systemId);
+	void releaseInputSource(InputSource* pSource);
+	
+	// DTDHandler
+	void notationDecl(const XMLString& name, const XMLString* publicId, const XMLString* systemId);
+	void unparsedEntityDecl(const XMLString& name, const XMLString* publicId, const XMLString& systemId, const XMLString& notationName);
+
+	// ContentHandler
+	void setDocumentLocator(const Locator* loc);
+	void startDocument();
+	void endDocument();
+	void startElement(const XMLString& uri, const XMLString& localName, const XMLString& qname, const Attributes& attributes);
+	void endElement(const XMLString& uri, const XMLString& localName, const XMLString& qname);
+	void characters(const XMLChar ch[], int start, int length);
+	void ignorableWhitespace(const XMLChar ch[], int start, int length);
+	void processingInstruction(const XMLString& target, const XMLString& data);
+	void startPrefixMapping(const XMLString& prefix, const XMLString& uri);
+	void endPrefixMapping(const XMLString& prefix);
+	void skippedEntity(const XMLString& name);
+	
+	// ErrorHandler
+	void warning(const SAXException& exc);
+	void error(const SAXException& exc);
+	void fatalError(const SAXException& exc);
+};
+
+
+} } // namespace Poco::XML
+
+
+#endif // SAX_DefaultHandler_INCLUDED