HOTFIX: Fix build issue with Akka 2.3.4 upgrade.

We had to upgrade our Hive 0.12 version as well to deal with a protobuf
conflict (both hive and akka have been using a shaded protobuf version).
This is testing a correctly patched version of Hive 0.12.

Author: Patrick Wendell <pwendell@gmail.com>

Closes #2756 from pwendell/hotfix and squashes the following commits:

cc979d0 [Patrick Wendell] HOTFIX: Fix build issue with Akka 2.3.4 upgrade.