iOS8下注冊push方式变更

if (IOS8_) {
    UIUserNotificationSettings *settings = [UIUserNotificationSettings settingsForTypes:(UIRemoteNotificationTypeBadge
                                                                                         |UIRemoteNotificationTypeSound
                                                                                         |UIRemoteNotificationTypeAlert)
                                                                             categories:nil];
    [application registerUserNotificationSettings:settings];
    [application registerForRemoteNotifications];
} else {
    [application registerForRemoteNotificationTypes:UIRemoteNotificationTypeAlert|UIRemoteNotificationTypeSound|UIRemoteNotificationTypeBadge];
}