title: Is there an ESLint rule to align `=` on assignments
body: <p>I'm looking for a rule which aligns all <code>=</code> on assignments.</p>
  
  <p>Something like this would be positive:</p>
  
  <pre><code>var foo       = 12;
  var barfoo    = 21;
  var barfoobar = 22;
  </code></pre>
  
  <p>Something like this would be negative:</p>
  
  <pre><code>var foo = 12;
  var barfoobar = 21;
  </code></pre>
  
  <p>Rubocop has a rule called <code>ForceEqualSignAlignment</code> for exactly this. I wonder if there is something like that for <code>ESLint</code>?</p>