Cleanup old incubator references left behind.

Couple references to when the project was in the incubator are still
in the codebase, removing and updating pom to point to correct mailing
list.

From: Jake Farrell <jfarrell@apache.org>
Review: https://reviews.apache.org/r/17032
Fixed a bug in the log recover test.

A wrong quorum size was used.

From: Jie Yu <yujie.jay@gmail.com>
Review: https://reviews.apache.org/r/17036