fluent/fluentd — pull request #428 by tagomoris (2014-09-16 11:20:54+00:00)
Title: Implementation of guaranteed delivery from ForwardOutput to ForwardInput

This patch provides "At least once" transferring on out/in-forward protocol.

This pull request is re-request of https://github.com/fluent/fluentd/pull/422.
And added patches below:
* rebase w/ v0.12 code
* use `chunk.unique_id` as ack value
* implicit configuration variable: extend_internal_protocol
* assume from other configuration values
* default ack timeout: 190secs from linux SYN_ACK defaults
* raise error for ack timeout to retry to send