[ios] UILabel with two different color text

# Usage

// Sample
private lazy var titleLabel: UILabel = {
	let label = UILabel()
	label.textColor = UIColor.lightGray
	label.font = UIFont.systemFont(ofSize: 16)
	label.numberOfLines = 0
	return label
}()

let red = "red"
let blue = "blue"
let green = "green"
let stringValue = "\(red)\n\(blue)\n&\n\(green)"

let attributedString: NSMutableAttributedString = NSMutableAttributedString(string: stringValue)

attributedString.setColor(color: UIColor.red, forText: red)   // or use direct value for text "red"
attributedString.setColor(color: UIColor.green, forText: green)   // or use direct value for text "blue"
attributedString.setColor(color: UIColor.blue, forText: blue)   // or use direct value for text "green"

attributedString.setFont(font: UIFont.systemFont(ofSize: 24), forText: green)

label.attributedText = attributedString

# Extension Sample

// Extension.
extension NSMutableAttributedString {
	func setColor(color: UIColor, forText stringValue: String) {
		let range: NSRange = self.mutableString.range(of: stringValue, options: .caseInsensitive)
		self.addAttribute(NSAttributedString.Key.foregroundColor, value: color, range: range)
	}

	func setFont(font: UIFont, forText stringValue: String) {
		let range: NSRange = self.mutableString.range(of: stringValue, options: .caseInsensitive)
		self.addAttribute(NSAttributedString.Key.font, value: font, range: range)
	}
}