Changelog

Unreleased

Implemented version and verifier in the API
Added API documentation \o/ (still a long way to go though)
Reworked Key API. It now uses type-level programming to distinguish key purposes, in the hope you'll never ever confuse them.
New features for file transfer
- File acks are not sent automatically anymore, the receiver has to accept an offer now.
- Existing files are not overwritten without permission
Internal improvements in Transit implementation. Little API changed except for the Keys.
Internal rewrite of the core. This resulted in no public API changes except that the receiver is now TryStream instead of Stream (error handling, yay).
Progress reporting support during transfers
send-many got improved

Merged Transit/Transfer implementation from @vu3rdd and made it work.
Rewrote Wormhole API (and parts of Transit/Transfer as well)
- Everything is async now (using async_std), there are no other (i.e. blocking) implementations.
- The API exposed from core got flipped on its head too in the process.
Moved IO layer into core; ported it from ws to async-tungstenite. Removed all tokio dependencies.
Many other refactorings, thrown stuff around, in the hope of improving things.
- Together with the changes noted above, the io::* modules got removed, as well as their Cargo feature flags (and dependencies).
- There is only one feature flag left, it's for the binary.
A bit of progress on the CLI side
- Added an experimental send-many command. It will create a code and then simply send the file over and over again in a loop. Might be useful.