* Synchronization via Dropbox.
* By using rust-bcrypt, we were able to ditch the unmaintained `rust-crypto`.
* Increased the `bcrypt` cost.
* Applied `clippy` proposals.
* Using the latest j4rs and its maven dependencies download-during-build feature, the size of the `rust-keylock-ui` crate got small and it was possible to publish it in the crates.io