A Swift extension for creating a UIBezierPath with smooth rounded corners that will match the iPhone X.
+[UIBezierPath bezierPathWithRoundedRect:cornerRadius:] will also give you smooth corners, but does not allow you to specify the radius for each corner individually - this does.
Based on everdrone/react-native-super-ellipse-mask + sugarmo/SGMSuperEllipsePath and converted to Swift.
Note: In order to match the iPhone X corner radius I used a value of 38.5 that was found by Kyle Bashour.
