Added support for the GenerateLibraryNamespace option in the C# generator.

src/Generator/Generators/CSharp/CSharpTextTemplate.cs

@@ -52,11 +52,15 @@ namespace Cxxi.Generators.CSharp
             WriteLine("using System.Runtime.InteropServices;");
             NewLine();
 
+            if (Options.GenerateLibraryNamespace)
+            {
                 WriteLine("namespace {0}", SafeIdentifier(Driver.Options.LibraryName));
                 WriteStartBraceIndent();
+            }
 
             GenerateDeclarations();
 
+            if (Options.GenerateLibraryNamespace)
                 WriteCloseBraceIndent();
         }