MINOR: Update the link to the Raft paper in docs
Update the link to the Raft paper pointing to the Usenix conference link.
old broken link:
new link:
Reviewers: Boyang Chen Konstantine Karantasis
<p>
There are a rich variety of algorithms in this family including ZooKeeper's
<a href="http://web.archive.org/web/20140602093727/http://www.stanford.edu/class/cs347/reading/zab.pdf">Zab</a>,
- <a href="https://ramcloud.stanford.edu/wiki/download/attachments/11370504/raft.pdf">Raft</a>,
+ <a href="https://www.usenix.org/system/files/conference/atc14/atc14-paper-ongaro.pdf">Raft</a>,
and <a href="http://pmg.csail.mit.edu/papers/vr-revisited.pdf">Viewstamped Replication</a>.
The most similar academic publication we are aware of to Kafka's actual implementation is
<a href="http://research.microsoft.com/apps/pubs/default.aspx?id=66814">PacificA</a> from Microsoft.
