Vendored dependencies.
Modern gitignore
Perform Xcode’s upgrade check
Remove code signing entitlements
Sate Xcode with a 568h default image
Ditch Google logo image
Fix random formatter warning
Remove unused file
Modernized, retina non-icon artwork assets
Bump to 6.0 deployment, fix minor resulting deprecations.
3.1.3 support is no longer a concern.
Use modern modal presentation methods