ES 1.2.x compatablity changes

To deal with ES HTTP / REST refactorings:

* elasticsearch/elasticsearch@05d46f80f21d109947729eac1a9edad1d5f0e2e0
* elasticsearch/elasticsearch@5156c3edf05feda4a18d510ed484c4a70486698e
Update tests
Version bump
Merge pull request #14 from xyu/es1.2-compat

Compatibility update for ES 1.2.x