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/UnicodeConverter.h

@@ -0,0 +1,141 @@
+//
+// UnicodeConverter.h
+//
+// Library: Foundation
+// Package: Text
+// Module:  UnicodeConverter
+//
+// Definition of the UnicodeConverter class.
+//
+// Copyright (c) 2006, Applied Informatics Software Engineering GmbH.
+// and Contributors.
+//
+// SPDX-License-Identifier:	BSL-1.0
+//
+
+
+#ifndef Foundation_UnicodeConverter_INCLUDED
+#define Foundation_UnicodeConverter_INCLUDED
+
+
+#include "Poco/Foundation.h"
+#include "Poco/UTFString.h"
+
+
+namespace Poco {
+
+
+class Foundation_API UnicodeConverter
+	/// A convenience class that converts strings from
+	/// UTF-8 encoded std::strings to UTF-16 or UTF-32 encoded std::wstrings
+	/// and vice-versa.
+	///
+	/// This class is mainly used for working with the Unicode Windows APIs
+	/// and probably won't be of much use anywhere else ???
+{
+public:
+	static void convert(const std::string& utf8String, UTF32String& utf32String);
+		/// Converts the given UTF-8 encoded string into an UTF-32 encoded wide string.
+
+	static void convert(const char* utf8String,  std::size_t length, UTF32String& utf32String);
+		/// Converts the given UTF-8 encoded character sequence into an UTF-32 encoded wide string.
+
+	static void convert(const char* utf8String, UTF32String& utf32String);
+		/// Converts the given zero-terminated UTF-8 encoded character sequence into an UTF-32 encoded wide string.
+
+	static void convert(const std::string& utf8String, UTF16String& utf16String);
+		/// Converts the given UTF-8 encoded string into an UTF-16 encoded wide string.
+
+	static void convert(const char* utf8String,  std::size_t length, UTF16String& utf16String);	
+		/// Converts the given UTF-8 encoded character sequence into an UTF-16 encoded wide string.
+
+	static void convert(const char* utf8String, UTF16String& utf16String);	
+		/// Converts the given zero-terminated UTF-8 encoded character sequence into an UTF-16 encoded wide string.
+
+	static void convert(const UTF16String& utf16String, std::string& utf8String);
+		/// Converts the given UTF-16 encoded wide string into an UTF-8 encoded string.
+
+	static void convert(const UTF32String& utf32String, std::string& utf8String);
+		/// Converts the given UTF-32 encoded wide string into an UTF-8 encoded string.
+
+	static void convert(const UTF16Char* utf16String,  std::size_t length, std::string& utf8String);
+		/// Converts the given zero-terminated UTF-16 encoded wide character sequence into an UTF-8 encoded string.
+
+	static void convert(const UTF32Char* utf16String, std::size_t length, std::string& utf8String);
+		/// Converts the given zero-terminated UTF-32 encoded wide character sequence into an UTF-8 encoded string.
+
+	static void convert(const UTF16Char* utf16String, std::string& utf8String);
+		/// Converts the given UTF-16 encoded zero terminated character sequence into an UTF-8 encoded string.
+
+	static void convert(const UTF32Char* utf32String, std::string& utf8String);
+		/// Converts the given UTF-32 encoded zero terminated character sequence into an UTF-8 encoded string.
+
+	template <typename F, typename T>
+	static void toUTF32(const F& f, T& t)
+	{
+		convert(f, t);
+	}
+
+	template <typename F, typename T>
+	static void toUTF32(const F& f, std::size_t l, T& t)
+	{
+		convert(f, l, t);
+	}
+
+	template <typename F, typename T>
+	static void toUTF16(const F& f, T& t)
+	{
+		convert(f, t);
+	}
+
+	template <typename F, typename T>
+	static void toUTF16(const F& f, std::size_t l, T& t)
+	{
+		convert(f, l, t);
+	}
+
+	template <typename F, typename T>
+	static void toUTF8(const F& f, T& t)
+	{
+		convert(f, t);
+	}
+
+	template <typename F, typename T>
+	static void toUTF8(const F& f, std::size_t l, T& t)
+	{
+		convert(f, l, t);
+	}
+
+	template <typename T>
+	static T to(const char* pChar)
+	{
+		T utfStr;
+		Poco::UnicodeConverter::convert(pChar, utfStr);
+		return utfStr;
+	}
+
+
+	template <typename T>
+	static T to(const std::string& str)
+	{
+		T utfStr;
+		Poco::UnicodeConverter::convert(str, utfStr);
+		return utfStr;
+	}
+
+	template <typename T>
+	static std::size_t UTFStrlen(const T* ptr)
+		/// Returns the length (in characters) of a zero-terminated UTF string.
+	{
+		if (ptr == 0) return 0;
+		const T* p;
+		for (p = ptr; *p; ++p);
+		return p - ptr;
+	}
+};
+
+
+} // namespace Poco
+
+
+#endif // Foundation_UnicodeConverter_INCLUDED