title: Restrict stylelint to only css and scss files
body: <p>I'm trying to configure <a href="https://github.com/stylelint" rel="noreferrer">stylelint</a> to <em>only</em> lint my CSS and/or SCSS files. I'm extending <a href="https://github.com/stylelint/stylelint-config-recommended" rel="noreferrer">stylelint-config-recommended</a> but by default it seems to be processing loads of other files as well as the .css and .scss ones I want to lint.</p>
  
  <p>Examples of files I don't want to include:</p>
  
  <ul>
  <li>.js</li>
  <li>.cshtml</li>
  </ul>
  
  <p>Exmples output from the CLI</p>
  
  <pre><code>debug.log
   1:67  ×  Unknown word   CssSyntaxError
  
  local.log
   21:21  ×  Missed semicolon   CssSyntaxError
  
  package-lock.json
   3:21  ×  Missed semicolon   CssSyntaxError
  
  package.json
   3:21  ×  Missed semicolon   CssSyntaxError
  
  personal.json
   3:40  ×  Missed semicolon   CssSyntaxError
  
  Program.cs
   1:1  ×  Unknown word   CssSyntaxError
  
  README.md
   11:51  ×  Unclosed bracket   CssSyntaxError
  
  reviewers.csproj
   1:1  ×  Unknown word   CssSyntaxError
  
  reviewers.csproj.user
   1:1  ×  Unknown word   CssSyntaxError
  
  reviewers.sln
   14:4  ×  Unknown word   CssSyntaxError
  </code></pre>
  
  <p>.stylelintrc</p>
  
  <pre><code>{
    "extends": "stylelint-config-recommended"
  }
  </code></pre>
  
  <p>.stylelintignore</p>
  
  <pre><code>node_modules
  bin
  obj
  *.js
  *.map
  </code></pre>