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/LocatorImpl.h

@@ -0,0 +1,88 @@
+//
+// LocatorImpl.h
+//
+// Library: XML
+// Package: SAX
+// Module:  SAX
+//
+// An implementation of the SAX Locator interface.
+//
+// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
+// and Contributors.
+//
+// SPDX-License-Identifier:	BSL-1.0
+//
+
+
+#ifndef SAX_LocatorImpl_INCLUDED
+#define SAX_LocatorImpl_INCLUDED
+
+
+#include "Poco/XML/XML.h"
+#include "Poco/SAX/Locator.h"
+#include "Poco/XML/XMLString.h"
+
+
+namespace Poco {
+namespace XML {
+
+
+class XML_API LocatorImpl: public Locator
+	/// Provide an optional convenience implementation of Locator.
+{
+public:
+	LocatorImpl();
+		/// Zero-argument constructor.
+		/// 
+		/// This will not normally be useful, since the main purpose of this class is 
+		/// to make a snapshot of an existing Locator.
+		
+	LocatorImpl(const Locator& loc);
+		/// Copy constructor.
+		/// 
+		/// Create a persistent copy of the current state of a locator. When the original 
+		/// locator changes, this copy will still keep the original values (and it can be 
+		/// used outside the scope of DocumentHandler methods).
+
+	~LocatorImpl();
+		/// Destroys the Locator.
+		
+	LocatorImpl& operator = (const Locator& loc);
+		/// Assignment operator.
+
+	XMLString getPublicId() const;
+		/// Return the saved public identifier.
+		
+	XMLString getSystemId() const;
+		/// Return the saved system identifier.
+
+	int getLineNumber() const;
+		/// Return the saved line number (1-based).
+		
+	int getColumnNumber() const;
+		/// Return the saved column number (1-based).
+		
+	void setPublicId(const XMLString& publicId);
+		/// Set the public identifier for this locator.
+
+	void setSystemId(const XMLString& systemId);
+		/// Set the system identifier for this locator.
+
+	void setLineNumber(int lineNumber);
+		/// Set the line number for this locator (1-based).
+
+	void setColumnNumber(int columnNumber);
+		/// Set the column number for this locator (1-based).
+
+private:
+	XMLString _publicId;
+	XMLString _systemId;
+	int _lineNumber;
+	int _columnNumber;
+};
+
+
+} } // namespace Poco::XML
+
+
+#endif // SAX_LocatorImpl_INCLUDED