Works together with https://github.com/bzhoek/handoff-ios to demonstrate Handoff and the Ubiquity key-value store.

For ubiquity to work, both .entitlements files need to have the same value for com.apple.developer.ubiquity-kvstore-identifier, i.e. $(TeamIdentifierPrefix)com.zilverline.classroom.

Actual updates appear to take ~3 seconds.

Simulating Esc to interrupt Keynote breaks the sandbox https://stackoverflow.com/questions/47503858/cocoa-swift-simulate-key-press-by-when-clicking-a-button.

• [] Conditional key simulation