Update SvgDocument.cs

1. Added XML Header, this is conform according to https://www.w3.org/TR/SVG/struct.html
2. Added support for removing Byte Order Mark (BOM), this needed in some cases, eg. if the SVG is used as SSI (Server Side Include) in IIS (Internet Information Server).

Source/SvgDocument.cs

@@ -484,10 +484,10 @@ namespace Svg
 					renderer.SetBoundable(new GenericBoundable(0, 0, bitmap.Width, bitmap.Height));
 
 					//EO, 2014-12-05: Requested to ensure proper zooming (draw the svg in the bitmap size, ==> proper scaling)
-					//EO, 2015-01-09, Added GetDimensions to use its returned size instead of this.Width and this.Height (request of Icarrere).
+					//EO, 2015-01-09, Added GetDimensions to use its returned size instead of this.Width and this.Height (request of Icarrere).
                     //BBN, 2015-07-29, it is unnecassary to call again GetDimensions and transform to 1x1
                     //JA, 2015-12-18, this is actually necessary to correctly render the Draw(rasterHeight, rasterWidth) overload, otherwise the rendered graphic doesn't scale correctly
-                    SizeF size = this.GetDimensions();
+                    SizeF size = this.GetDimensions();
 					renderer.ScaleTransform(bitmap.Width / size.Width, bitmap.Height / size.Height);
 
 					//EO, 2014-12-05: Requested to ensure proper zooming out (reduce size). Otherwise it clip the image.
@@ -575,12 +575,12 @@ namespace Svg
             }
         }
 
-        public void Write(Stream stream)
+        public void Write(Stream stream, bool useBom = true)
         {
 
-            var xmlWriter = new XmlTextWriter(stream, Encoding.UTF8);
+            var xmlWriter = new XmlTextWriter(stream, useBom ? Encoding.UTF8 : new System.Text.UTF8Encoding(false));
             xmlWriter.Formatting = Formatting.Indented;
-
+            xmlWriter.WriteStartDocument();
             xmlWriter.WriteDocType("svg", "-//W3C//DTD SVG 1.1//EN", "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd", null);
             
             if (!String.IsNullOrEmpty(this.ExternalCSSHref))
@@ -591,11 +591,11 @@ namespace Svg
             xmlWriter.Flush();
         }
 
-        public void Write(string path)
+        public void Write(string path, bool useBom = true)
         {
             using (var fs = new FileStream(path, FileMode.Create, FileAccess.Write))
             {
-                this.Write(fs);
+                this.Write(fs, useBom);
             }
         }
     }