title: ng new not working anymore on one windows 10 machine
body: <p><code>ng new my-app</code> results in "Schematic input does not validate against the Schema: </p>
  
  <pre><code>{
      "version":"6.2.4",
      "skipGit":false,
      "experimentalIvy":false,
      "skipInstall":false,
      "linkCli":false,
      "commit":true,
      "newProjectRoot":"projects",
      "inlineStyle":false,
      "inlineTemplate":false,
      "routing":false,
      "prefix":"app",
      "style":"css",
      "skipTests":false,
      "createApplication":true
  }
  
  Errors:
  
  Data path "" should have required property 'name'."
  </code></pre>
  
  <p>All worked nice a week ago, the problem is not reproducable on a windows 7 machine.
  The problem remains even after a fresh install of nodejs and @angular/cli@latest.
  Same error message (including version 6.2.4 !?) with @angular/cli@6.0.0.
  Any suggestion would be appreciated.</p>