title: Prevent svcutil from generating "EmitDefaultValue=false" attributes
body: <p>I've recently been trying to generate data contracts from xsd files, using svcutil like this:</p>
  
  <pre><code>svcutil.exe /t:code /dconly /out:MyContract.cs /n:*,My.Namespace MyDataDefinition.xsd
  </code></pre>
  
  <p>The XSD mostly consists of definitions like this:</p>
  
  <pre><code>&lt;xsd:complexType name="SomeComplexObjectType"&gt;
      &lt;xsd:sequence&gt;
          &lt;xsd:element name="FirstData" type="xsd:string" minOccurs="0" /&gt;
          &lt;xsd:element name="SecondData" type="xsd:string" minOccurs="0" /&gt;
      &lt;/xsd:sequence&gt;
  &lt;/xsd:complexType&gt;
  </code></pre>
  
  <p>svcutil generates something like this:</p>
  
  <pre><code>[System.Diagnostics.DebuggerStepThroughAttribute()]
  [System.CodeDom.Compiler.GeneratedCodeAttribute("System.Runtime.Serialization", "3.0.0.0")]
  [System.Runtime.Serialization.DataContractAttribute(Name="SomeComplexObjectType")]
  public partial class PersonInfo : object, System.Runtime.Serialization.IExtensibleDataObject
  {
      private string FirstDataField;
      private string SecondDataField;
  
      [System.Runtime.Serialization.DataMemberAttribute(EmitDefaultValue=false)]
      public string FirstData
      {
          get
          {
              return this.FirstDataField;
          }
          set
          {
              this.FirstDataField= value;
          }
      }
  
      [System.Runtime.Serialization.DataMemberAttribute(EmitDefaultValue=false)]
      public string SecondData
      {
          get
          {
              return this.SecondDataField;
          }
          set
          {
              this.SecondDataField= value;
          }
      }
  }
  </code></pre>
  
  <p>Which works fine, however, the "EmitDefaultValue=false" attributes are not necessary.  Not to mention that it introduces a lot of noise into the wsdl, adding stuff like this:</p>
  
  <pre><code>&lt;xsd:element minOccurs="0" name="FirstData" nillable="true" type="xsd:string"&gt;
      &lt;xsd:annotation&gt;
          &lt;xsd:appinfo&gt;
              &lt;DefaultValue xmlns="http://schemas.microsoft.com/2003/10/Serialization/" EmitDefaultValue="false"/&gt;
          &lt;/xsd:appinfo&gt;
      &lt;/xsd:annotation&gt;
  &lt;/xsd:element&gt;
  </code></pre>
  
  <p>Currently I'm just hand-editing the generated contract, but that is not ideal from a maintenance standpoint.</p>
  
  <p>Does anyone know how to prevent svcutil from automatically generating these EmitDefaultValue=false attributes?</p>