Add 'st', 'nd', 'rd' and 'th' to data strings: May 17th, April 2rd...

nice_date.swift

let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "MMMM d"

private func daySuffix(date: NSDate) -> String {
    let calendar = NSCalendar.currentCalendar()
    let dayOfMonth = calendar.component(.Day, fromDate: date)
    switch dayOfMonth {
        case 1: fallthrough
        case 21: fallthrough
        case 31: return "st"
        case 2: fallthrough
        case 22: return "nd"
        case 3: fallthrough
        case 23: return "rd"
        default: return "th"
    }
}

let dateComp = NSDateComponents()
dateComp.day = -10

let date = NSCalendar.currentCalendar().dateByAddingComponents(dateComp, toDate: NSDate(), options: [])!
dateFormatter.stringFromDate(date)+daySuffix(date)