reorganizing the code

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>

src/bindings/dotnet/Microsoft.Z3/Z3Exception.cs

@@ -0,0 +1,44 @@
+/*++
+Copyright (c) 2012 Microsoft Corporation
+
+Module Name:
+
+    Exception.cs
+
+Abstract:
+
+    Z3 Managed API: Exceptions
+
+Author:
+
+    Christoph Wintersteiger (cwinter) 2012-03-15
+
+Notes:
+    
+--*/
+
+using System;
+
+namespace Microsoft.Z3
+{
+  /// <summary>
+  /// The exception base class for error reporting from Z3
+  /// </summary>
+  public class Z3Exception : Exception
+  {
+    /// <summary>
+    /// Constructor.
+    /// </summary>
+    public Z3Exception() : base() { }
+
+    /// <summary>
+    /// Constructor.
+    /// </summary>
+    public Z3Exception(string message) : base(message) { }
+
+    /// <summary>
+    /// Constructor.
+    /// </summary>
+    public Z3Exception(string message, System.Exception inner) : base(message, inner) { }
+  }
+}