Generate qr code from existing entry

[ghost]

To "sync" with other devices and easily transfer

[hye]

sync is not safe while transferring , that's why Google Authenticator did not add the function in earlier versions. (And they use word migration in latest version) The author did not even programmed use iCloud to sync, but wrote

Off the Grid: The app never connects to the internet, and your secret keys never leave your device.

in Readme.md, maybe he thought that as well.

[ghost]

I didnt thought about syncing via cloud but rather generating a QR code from an existing entry which then can be scanned by another devices authenticator to get the code

[antedebaas]

see #344