<Target Name="BeforeBuild">
    <Message Text="Transforming Web.config from Web.$(Configuration).config" Importance="high" />
    <MakeDir Directories="bin" Condition="!Exists('bin')" />
    <TransformXml Source="Web.Config" Transform="Web.$(Configuration).config" Destination="bin\$(TargetFileName).config" StackTrace="true" />
</Target>