Change Notification variable to avoid ambiguous error

[mrhaxic]

Hello, Library should use another variable name instead of Notification in the below lines

public struct Notification {
    static let titleFont = UIFont.boldSystemFont(ofSize: 14)
    static let subtitleFont = UIFont.systemFont(ofSize: 13)

    static let animationDuration: TimeInterval = 0.3 // second(s)
    public static let exhibitionDuration: TimeInterval = 5.0 // second(s)

}

to avoid the error of 'Notification' is ambiguous for type lookup in this.

Thanks