fixed 'none' errors for SvgUnits

Source/DataTypes/SvgUnit.cs

@@ -165,13 +165,7 @@ namespace Svg
             }
         }
 
-        /// <summary>
-        /// Indicates whether this instance and a specified object are equal.
-        /// </summary>
-        /// <param name="obj">Another object to compare to.</param>
-        /// <returns>
-        /// true if <paramref name="obj"/> and this instance are the same type and represent the same value; otherwise, false.
-        /// </returns>
+		#region Equals and GetHashCode implementation
 		public override bool Equals(object obj)
 		{
 			if (obj == null) return false;
@@ -181,10 +175,33 @@ namespace Svg
             return (unit.Value == this.Value && unit.Type == this.Type);
 		}
 		
+		public bool Equals(SvgUnit other)
+		{
+			return this._type == other._type && (this._value == other._value);
+		}
+		
 		public override int GetHashCode()
 		{
-            return base.GetHashCode();
+			int hashCode = 0;
+			unchecked {
+				hashCode += 1000000007 * _type.GetHashCode();
+				hashCode += 1000000009 * _value.GetHashCode();
+				hashCode += 1000000021 * _isEmpty.GetHashCode();
+				hashCode += 1000000033 * _deviceValue.GetHashCode();
+			}
+			return hashCode;
+		}
+		
+		public static bool operator ==(SvgUnit lhs, SvgUnit rhs)
+		{
+			return lhs.Equals(rhs);
+		}
+		
+		public static bool operator !=(SvgUnit lhs, SvgUnit rhs)
+		{
+			return !(lhs == rhs);
 		}
+		#endregion
 
         public override string ToString()
         {

Source/Document Structure/SvgUse.cs

@@ -49,6 +49,8 @@ namespace Svg
         /// </summary>
         public SvgUse()
         {
+        	this.X = 0;
+        	this.Y = 0;
         }
 
         public override System.Drawing.Drawing2D.GraphicsPath Path