Improve documentation for PdfSubpath.Rectangle(...).

src/UglyToad.PdfPig.Core/PdfSubpath.cs

@@ -160,9 +160,9 @@
                 throw new ArgumentNullException("LineTo(): currentPosition is null.");
             }
         }
-        
+
         /// <summary>
-        /// Adds 4 <see cref="Line"/>s forming a rectangle to the path.
+        /// Add a rectangle following the pdf specification (m, l, l, l, c) path. A new subpath is created.
         /// </summary>
         public void Rectangle(double x, double y, double width, double height)
         {
@@ -174,8 +174,6 @@
             CloseSubpath();                     // h
             IsDrawnAsRectangle = true;
         }
-        
-        internal void QuadraticCurveTo(double x1, double y1, double x2, double y2) { }
 
         /// <summary>
         /// Add a <see cref="BezierCurve"/> to the path.