Use UIAlertController for iOS 8 and higher instead of deprecated UIAlertView

[funnel20]

UIAlertView is deprecated in iOS 8.0.
There is still one entry in IASKAppSettingsViewController (and 1 in the demo's MainViewController).
Obviously UIAlertView should stay in to support iOS 7 and lower.
However, it would be appropriate to use UIAlertController when available (for iOS 8 and higher).

Here is my suggestion to change the ELSE condition of the MailComposer check in 'didSelectRowAtIndexPath:':

Existing code:

UIAlertView *alert = [[UIAlertView alloc]
                      initWithTitle:NSLocalizedString(@"Mail not configured", @"InAppSettingsKit")
                      message:NSLocalizedString(@"This device is not configured for sending Email. Please configure the Mail settings in the Settings app.", @"InAppSettingsKit")
                      delegate: nil
                      cancelButtonTitle:NSLocalizedString(@"OK", @"InAppSettingsKit")
                      otherButtonTitles:nil];
[alert show];

New code:

if ([UIAlertController class]) {
    // >= iOS 8
    UIAlertController *alert = [UIAlertController alertControllerWithTitle:NSLocalizedString(@"Mail not configured", @"InAppSettingsKit")
                                                                   message:NSLocalizedString(@"This device is not configured for sending Email. Please configure the Mail settings in the Settings app.", @"InAppSettingsKit")
                                                            preferredStyle:UIAlertControllerStyleAlert];

    UIAlertAction *cancelAction = [UIAlertAction actionWithTitle:NSLocalizedString(@"OK", @"InAppSettingsKit")
                                                           style:UIAlertActionStyleCancel
                                                         handler:^(UIAlertAction * action) {
                                                             // Do nothing
                                                         }];

    [alert addAction:cancelAction];

    [self presentViewController:alert
                       animated:YES
                     completion:nil];
}
else {
    // < iOS 8
    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:NSLocalizedString(@"Mail not configured", @"InAppSettingsKit")
                                                    message:NSLocalizedString(@"This device is not configured for sending Email. Please configure the Mail settings in the Settings app.", @"InAppSettingsKit")
                                                   delegate:nil
                                          cancelButtonTitle:NSLocalizedString(@"OK", @"InAppSettingsKit")
                                          otherButtonTitles:nil];
    [alert show];
}