Fix crash when creating null terminator in updateRichText (writing out of bounds)

src/interface/RichLabel.cpp

@@ -55,7 +55,7 @@ void RichLabel::updateRichText()
 		int originalTextPos = 0;
 		char * originalText = new char[textSource.length()+1];
 		std::copy(textSource.begin(), textSource.end(), originalText);
-		originalText[textSource.length()+1] = 0;
+		originalText[textSource.length()] = 0;
 
 		int stackPos = -1;
 		RichTextRegion * regionsStack = new RichTextRegion[256];