v3.0.0

Fixes:

• Replace socketTimeout with bodyTimeout (#460).
• Replace keepAlive option with pipelining: 0 (#459).
• Rename idleTimeout option to keepAliveTimeout (#461).
• Retry idempotent with original body (#471).
• Add writableNeedDrain support to Client.stream (#442).
• Free parser when detaching.
• Throw if passed maxKeepAliveTimeout, idleTimeout, or socketTimeout.

Improvements:

• Add trailers support to Client.request (#493).
• Misc refactoring.