title: Cocoapods fails to lint with swift 3.0 errors even though project is swift 2.3
body: <p>I have a private pod, and I am trying to do a <code>pod repo push</code> but its rejecting it because of errors that could only happen in <code>Swift3.0</code> e.g <code>@noescape is the default and is deprecated</code>. I use --allow-warnings but there are also errors beside this warning, this is just the most obvious <code>Swift3.0</code> error. </p>
  
  <p>The project itself is in <code>Swift2.3</code>, I have the legacy flag setup in all targets, not to mention I have pushed a new spec just a few days ago and I am unaware what could have changed. The project builds fine in <code>Xcode</code>.</p>
  
  <p>If its relevant, the pod that happens to error out is the <code>Result</code> one, but I am sure it could be any of them.</p>