Update mapping to provide a try api in SvgDocument

Make Clone SvgAttribute internal
Add clone method on svg Attribute, that returns instead of out parameter

Author: mrvux

Source/SharpDX.Direct2D1/Mapping-direct2d1.xml

@@ -494,8 +494,12 @@
     <map param="ID2D\dDeviceContext5::CreateColorContextFromSimpleColorProfile::colorContext" attribute="out fast"/>
     <map param="ID2D\dEffectContext2::CreateColorContextFromDxgiColorSpace::colorContext" attribute="out fast"/>
     <map param="ID2D\dEffectContext2::CreateColorContextFromSimpleColorProfile::colorContext" attribute="out fast"/>
+    
+    <!-- Svg documents and elements -->
+    <map method="ID2D1SvgDocument::FindElementById" hresult="true" check="false" visibility="private" name="TryFindElementById_"/>
+    <map method="ID2D1SvgAttribute::Clone" visibility="internal" />
 
-     <!--
+    <!--
     // *****************************************************************
     // D2D1 Functions
     // *****************************************************************

Source/SharpDX.Direct2D1/SvgAttribute.cs

@@ -0,0 +1,21 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace SharpDX.Direct2D1
+{
+    public partial class SvgAttribute
+    {
+        /// <summary>
+        /// Clones an svg attribute
+        /// </summary>
+        /// <returns></returns>
+        public SvgAttribute Clone()
+        {
+            SvgAttribute svgAttribute;
+            Clone(out svgAttribute);
+            return svgAttribute;
+        }
+    }
+}