title: Why do my TSLint rules result in errors when severity is set to "warning"?
body: <p>I'm trying IntelliJ to create warnings when following rule is broken:</p>
  
  <pre><code>    "no-cross-import": [
         false,
         {
          "root": "src",
          "ignoredSources": [
          "Spec\\.ts$"
          ],
          "allowed": {
            "patterns": [
            "legacy"
            ]
          },
          "severity": "warning"
       }
      ]
  </code></pre>
  
  <p>but it always results in an error.
  I've tried </p>
  
  <pre><code>  "defaultSeverity": "warning",
    "rules": {
       //some rules here
  </code></pre>
  
  <p>as a workaround but it also results in an error as seen in 
  <a href="https://i.stack.imgur.com/GGRRO.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/GGRRO.png" alt="screenshot"></a></p>