Automatically check for updates

[JJTech0130]

Persistently check from updates (from GitHub Releases?). Easiest method is probably via a GitHub API query like https://api.github.com/repos/JJTech0130/ValidationRelay/releases/latest

Once an updated IPA has been found, can use posix_spawn to launch TrollStore's root helper in the background to update the app.

Caveats:

• Will TrollStore's root helper automatically re-launch our app when the update is complete?
• Would require unsandboxing
• Will the TestFlightServiceExtension be properly removed and re-launched?

Alternatives:

• Build update mechanism into Installer
  • Would not allow updating when installed through "normal" TrollStore
• Use URL scheme
  • Would most likely require user interaction to complete update

[cameronaaron]

Fixed in
#8