Go-Ratchet 🛡️

Double ratchet algorithm implementation.

TODO

• Add docs for each function. Add comments for e.g. ratchetReceivingChain and ratchetSendingChain.
• Add tests.
• Reduce allocations count. For example, reuse slices for HKDF and encryption/decryption. Encrypt/Decrypt to array from stack.
• Create benchmarks to increase speed.