Add plugin release semi-automatic script

Closes #22
Update to Lucene 4.6.1 / Elasticsearch 1.0.0

Closes #18
Can not upgrade kuromoji plugin from elasticsearch 0.90.5

Due to fix [3790](https://github.com/elasticsearch/elasticsearch/issues/3790) in core, upgrading an analyzer provided as a plugin now fails.

See https://github.com/elasticsearch/elasticsearch/issues/5030 for details.

Issue is in elasticsearch core code but can be fixed in plugins by overloading `PreBuiltAnalyzerProviderFactory`,  `PreBuiltTokenFilterFactoryFactory`, `PreBuiltTokenizerFactoryFactory` or `PreBuiltCharFilterFactoryFactory ` when used.

Closes #21
(cherry picked from commit 3401c21)
prepare release elasticsearch-analysis-kuromoji-2.0.0
prepare for next development iteration