Add plugin release semi-automatic script

Closes #50.
(cherry picked from commit ecd4afc)
Update to rabbitmq client 3.2.3

Closes #53.

(cherry picked from commit 5355e2d2cd65117b144733e0a435a3e4941cf778)
Update to Lucene 4.6.1 / Elasticsearch 0.90.11

Closes #54.