title: VS 2015 "Dependency could not be resolved" error on vNext project compilation
body: <p>I am trying to add Newtonsoft.json nugget package to my project and getting the following error on compilation,</p>
  
  <p><strong>"NU1001 The dependency Newtonsoft.Json >= 7.0.1 could not be resolved."</strong></p>
  
  <p>It works fine if I install the package version &lt;= 6.0.6. I also tried running <strong>dnu restore</strong> (apparently worked for someone else) from the powershell in the root folder of the project. Same error. Also tried installing via Nugget manager and adding the package name directly in the project.json and letting the VS restore itself.</p>
  
  <p>I am trying to build on dnx451 framework beta8 version.</p>
  
  <p>Does any of the default Framework dependencies require the 6.0.6 version? If so, are there any workarounds to this. I have other projects that requires the latest nugget package and which when referred from the vNext project, throws reference mismatch errors.</p>
  
  <p>Appreciate any help!</p>