Updated README.md
Updated README.md

Added correct info on supported version
Added graylog radio deprecation info

Graylog2/graylog2-puppet,treydock/graylog2-puppet,Jimdo/graylog2-puppet,Jimdo/graylog2-puppet,treydock/graylog2-puppet,Graylog2/graylog2-puppet,Graylog2/graylog2-puppet,treydock/graylog2-puppet,Jimdo/graylog2-puppet