Added properties:
public static NSCharacterSet UrlFragmentAllowed { get; }
public static NSCharacterSet UrlHostAllowed { get; }
public static NSCharacterSet UrlPasswordAllowed { get; }
public static NSCharacterSet UrlPathAllowed { get; }
public static NSCharacterSet UrlQueryAllowed { get; }
public static NSCharacterSet UrlUserAllowed { get; }