title: SwiftLint: Exclude file for specific rule
body: <p>I'm trying to do something like this in my .swiftlint.yml file:</p>
  
  <pre><code>force_cast:
    severity: warning # explicitly
    excluded:
      - Dog.swift
  </code></pre>
  
  <p>I have this code and I don't like the force_try warning I'm getting for it:</p>
  
  <pre><code>let cell = tableView.dequeueReusableCellWithIdentifier(Constants.dogViewCellReuseIdentifier,
                                                                 forIndexPath: indexPath) as! DogViewCell
  </code></pre>
  
  <p>I want to suppress the warning for this file by excluding this file from the rule.</p>
  
  <p>Is there a way to do that ?</p>