title: Unexpected nil when using Chameleon's result to set UIView.backgroundColor
body: <p>I'm trying to use Chameleon to get analogous colors. The returned array of colors is not nil, each of the 5 elements are also not nil. However the code "tintView.backgroundColor = color" results in "Fatal error: Unexpectedly found nil while unwrapping an Optional value". The first picture shows the code and the non-nil 5 element array returned from a call to Chameleon. The 2nd picture shows the variable as copied from the global array (it's missing data)</p>
  
  <p><a href="https://i.stack.imgur.com/k32M8.png" rel="nofollow noreferrer">1</a></p>
  
  <p>I've tried setting Chameleon to use Swift 4 as well as Swift 4.2. No difference. I'm currently targeting iPhone 7 running IOS 11.4 What am I missing? Shouldn't this simply work?</p>
  
  <p>Pertinent part of Globals.swift:</p>
  
  <pre><code>  static var companionColors = ColorSchemeOf(.analogous, color: UIColor.flatYellowDark, isFlatScheme: true)
    static var complimentryColor = UIColor(complementaryFlatColorOf:selectedColor)
    static var initialColorName = "Yellow"
    static var selectedColor = UIColor.flatYellowDark {
        didSet {
            companionColors = ColorSchemeOf(.analogous, color: selectedColor, isFlatScheme: true)
            complimentryColor = UIColor(complementaryFlatColorOf:selectedColor)
          }
      }
  </code></pre>
  
  <p>CommonViewController:</p>
  
  <pre><code>  class CommonViewController: UIViewController {
      @IBOutlet weak var canvas: UIImageView!
      @IBOutlet weak var tintView: UIView!
  
      override func viewDidLoad() {
          super.viewDidLoad()
      }
  
      override func viewDidAppear(_ animated: Bool) {
        super.viewDidAppear(animated)
        let color = Globals.companionColors[1]
        tintView.backgroundColor = color
      }
    }
  </code></pre>
  
  <p>As mentioned the line 'tintView.backgroundColor = color' is throwing the error. Globals.companionColors contains 5 elements of type UIDeviceRGBColor* with RGBA values and a UIColor component. 'color' is an NSObject.</p>