v4.4.1

See full changelog here.

Commits:

• agent: prevent batch deletions from failing on one connection sql error (#628)
• agent: more strict parsing of TransportHost, tests (#629)
• extend HTTP2 transport (#632)
• refactor transport encoding, make client IO error "temporary" (#634)
• NaCL secretbox based on cryptonite (#636)
• lazy pad/unpad, secretbox encrypt/decrypt (#639)
• parameterize protocol by error type (#644)
• server_key_hash fields (#643)
• increase timeout for QUOTA errors
• 4.4.1