title: BinaryFormatter in netstandard 1.5
body: <p>According to the <a href="https://github.com/dotnet/corefx/blob/master/Documentation/architecture/net-platform-standard.md" rel="noreferrer">List of .NET CoreFx APIs and their associated .NET Platform Standard version</a>, System.Runtime.Serialization.Formatters is added into to the .NET Platform Standard since 1.3, which is cool, but when I try to create a .Net Core class library targeting netstandard1.5 under.Net Core RC2, I can't use it.</p>
  
  <p>The code is simple, just intending to declare a BinaryFormatter:</p>
  
  <pre><code>public class Problems {
      private System.Runtime.Serialization.Formatters.Binary.BinaryFormatter _formatter;
  }
  </code></pre>
  
  <p>Error is :</p>
  
  <blockquote>
    <p>Error CS0234 The type or namespace name 'Serialization' does not exist
    in the namespace 'System.Runtime' (are you missing an assembly
    reference?)</p>
  </blockquote>
  
  <p>Here is the project.json, which I did no modifications:</p>
  
  <pre><code>{
    "version": "1.0.0-*",
  
    "dependencies": {
      "NETStandard.Library": "1.5.0-rc2-24027",
    },
  
    "frameworks": {
      "netstandard1.5": {
        "imports": "dnxcore50"
      }
    }
  }
  </code></pre>
  
  <p>So, is there another package that I need depend on? And Why? Shouldn't a netstandard moniker be enough for all the APIs in the list?</p>