simplify silverlight support for the Serializable attribute

src/Numerics/Complex32.cs

@@ -71,9 +71,7 @@ namespace MathNet.Numerics
     /// Wikipedia</a>
     /// </para>
     /// </remarks>
-#if !SILVERLIGHT
     [Serializable]
-#endif
     [StructLayout(LayoutKind.Sequential)]
     public struct Complex32 : IFormattable, IEquatable<Complex32>, IPrecisionSupport<Complex32>
     {

src/Numerics/LinearAlgebra/Double/Matrix.cs

@@ -35,9 +35,7 @@ namespace MathNet.Numerics.LinearAlgebra.Double
     /// <summary>
     /// Defines the base class for <c>Matrix</c> classes.
     /// </summary>
-#if !SILVERLIGHT
     [Serializable]
-#endif
     public abstract partial class Matrix :
 #if SILVERLIGHT
    IFormattable, IEquatable<Matrix>

src/Numerics/LinearAlgebra/Double/Vector.cs

@@ -37,9 +37,7 @@ namespace MathNet.Numerics.LinearAlgebra.Double
     /// <summary>
     /// Defines the base class for <c>Vector</c> classes.
     /// </summary>
-#if !SILVERLIGHT
     [Serializable]
-#endif
     public abstract class Vector :
 #if SILVERLIGHT
     IFormattable, IEnumerable<double>, IEquatable<Vector>

src/Numerics/Permutation.cs

@@ -41,9 +41,7 @@ namespace MathNet.Numerics
     /// <summary>
     /// Class to represent a permutation for a subset of the natural numbers.
     /// </summary>
-#if !SILVERLIGHT
     [Serializable]
-#endif
     public class Permutation
     {
         #region fields

src/Numerics/Statistics/Histogram.cs

@@ -39,9 +39,7 @@ namespace MathNet.Numerics.Statistics
     /// A <see cref="Histogram"/> consists of a series of <see cref="Bucket"/>s, 
     /// each representing a region limited by a lower bound (exclusive) and an upper bound (inclusive).
     /// </summary>
-#if !SILVERLIGHT
     [Serializable]
-#endif
     public class Bucket :
 #if SILVERLIGHT
    IComparable<Bucket>
@@ -225,9 +223,7 @@ namespace MathNet.Numerics.Statistics
     /// <summary>
     /// A class which computes histograms of data.
     /// </summary>
-#if !SILVERLIGHT
     [Serializable]
-#endif
     public class Histogram
     {
         /// <summary>

src/Silverlight/SerializableAttribute.cs

@@ -0,0 +1,9 @@
+using System;
+
+namespace MathNet.Numerics
+{
+	[AttributeUsage(AttributeTargets.Class | AttributeTargets.Struct)]
+	public class SerializableAttribute : Attribute
+	{
+	}
+}

src/Silverlight/Silverlight.csproj

@@ -360,6 +360,7 @@
       <DependentUpon>Version.tt</DependentUpon>
     </Compile>
     <Compile Include="Properties\AssemblyInfo.cs" />
+    <Compile Include="SerializableAttribute.cs" />
     <Compile Include="SilverlightUtilities.cs" />
     <Compile Include="Threading\AggregateException.cs" />
     <Compile Include="Threading\Parallel.cs" />