Fixed an issue when rendering emojis and other unicode strings

[robertodias180]

Some emojist stoped working after update.
this code is the code I have

let messageStyle = Style {
    $0.font = UIFont.systemFont(ofSize: 12)
    $0.kerning = Kerning.point(0.3)
    $0.color = UIColor.bsBase
}
self.messageLabel.attributedText = "😇".set(style: messageStyle)

On version 2.0.1

On version 2.0.2+

Any clues what may have caused this?

[malcommac]

Thank you; just fixed it.

String.count returns the number of rendered characters in the string. Some emojis are a combination of two or more UTF characters that are rendered into one character, in order to allow for more emojis.
In order to get the actual length of the string for use in NSRange, I need to use NSAttributedString.length.