title: System.Drawing namespace missing in aspnetVnext core CLR
body: <p>System.drawing namespace is not available in the coreCLR . I want to resize the image in the server and return store it.  </p>
  
  <p>To give more context my application uses markdown for content edition . once the image is uploaded I want to resize and apply it in HTML . I am making an assembly to work with coreclr not on the desktop . </p>