v1.1.7

• Based on librdkafka v1.0.1
• Removed configs: queuing_strategy, offset_store_method, reconnect_backoff_jitter_ms
• Added new configs: reconnect_backoff_ms, reconnect_backoff_max_ms, max_poll_interval_ms, enable_idempotence, enable_gapless_guarantee
• get_stats decodes json to maps instead of proplists