Merge pull request #8 from mashhurs/change-api_key-type-to-password

Change api_key config type to password to prevent from leaks in debug logs.

set default_codec doc attribute

[skip ci] update gemspec summary

version bump for some docs fixes

bump patch level for doc generation

Update this plugin to the new event api 2.0 (#4)

- update .travis.yml
- uses the new accessor
- relax constraints for the logstash-core

dependency logstash-core-plugin-api ~> 1.0

dependency logstash-core >= 2.0.0.beta2 < 3.0.0

dependency logstash-core >= 2.0.0.snapshot < 3.0.0

bump version