added comment as per Scott feedback

MVMCoreUI/Atoms/Views/ProgressBar.swift

@@ -54,6 +54,7 @@ import Foundation
         if let thickness = json?.optionalCGFloatForKey("thickness") {
             self.thickness = thickness
         }
+        // as? Float returns nil, apple defect.
         if let percentage = json?["percent"] as? CGFloat {
             progress = Float(percentage/100.0)
         }