Fix AppleTV installation issue and update readme with AppleTV

[stuartw1]

Some suggested patches for AppleTV support. Please review and feel free to ask me to improve if they are not up to standard or reject if not worth merging :)

Change 1 - pkg-actions.m

Bypass the notification window for AppleTV devices so that installation does not hang. The AppleTV can't display the notification window so installation hangs, then has to be force quit by the user. The patch attempts to resolve this, though the information could also be printed to the logs. Support for bridgeOS or watchOS etc. could be added in a similar way if required.

Change 2 README.md

Add instructions to the readme for how to build a *.deb for AppleTV by modifying the target. Encourage further development for other more obscure devices.

Warning

I performed some build testing on my limited selection of devices and it appeared to work - though recommend you test to double check before releasing

[akemin-dayo]

Thank you for your contribution!

I've made two major changes in commit SHA1 12314a6 that supercede the functionality in this PR.

1. The CFUserNotification is now only displayed when the user is installing ASU using an APT frontend that implements the ${CYDIA} environment variable. This includes Cydia, Zebra, and Sileo to my knowledge.
2. The CFUserNotification no longer blocks the main thread, so the installation process will not get stuck until the notification is dismissed. (This was a massive oversight on my part in the original implementation. Somehow I completely missed Apple mentioning CFUserNotificationCreateRunLoopSource in their documentation when I was reading it the first time around…)

As a result, I'll be closing this PR, but I will try and add some basic tvOS build support in the form of an alternate Makefile or something, as well as updating the documentation accordingly.

That being said though, can you try testing my latest changes on your tvOS machine? Let me know how the installation process goes, as I uh… still don't own a tvOS device ;P

[stuartw1]

Thanks!

Just seen this - will try to take a look when I get a moment to take my tvOS machine out of the cupboard