add 'itunes' command to kick iOS 3 devices out of "connect to itunes" screen

[tihmstar]

Older iOS (tested on iPod2,1 iOS 3.1.3) can be activated just fine, but doesn't actually leave the "connect to itunes" screen with "just" activation.
In addition we need to tell lockdownd that 'iTunesHasConnected'.

This commit adds a subcommand for doing just that. By doing that, iOS 3 reaches Springboard and can be used without actually connecting to iTunes.

[nikias]

I think maybe we should just set the value once activation succeeded?

[tihmstar]

What if the activation doesn't succeed (because it's already activated), but the device is still in the "connect to itunes" screen?
I think unless you wanna debug all the different edge cases it's easier to just have a second command.

[nikias]

let's just set the value in all cases, even on failure? if it's already activated it would get rid of the screen, if activation fails it would still show the activation screen regardless of that value

[tihmstar]

I mean you can do it that way and (potentially) deal with it later in case unexpected issues arise.
Unfortunatelly i can't test all the edge cases anymore as the issue is so old.
I leave the final decision up to you.

Personally i'd just have a separate command for not having to deal with unexpected issues (in both pre-iOS 4 and post iOS4) later.