Merge pull request jhuangtw#46 from derekcollison/patch-1

Added NATS.io to pubsub section.

README.md

@@ -47,7 +47,7 @@ See also: [System Design Primer](https://github.com/donnemartin/system-design-pr
 | Dremel       |   [bigquery](https://cloud.google.com/bigquery/)     | Apache Drill, [Presto](https://prestodb.io), Spark(sort-of), | AWS Athena, [Redshift Spectrum](https://aws.amazon.com/redshift/spectrum/) |
 | Dremel UI    |             | [Redash](https://github.com/getredash/redash), [Metabase](https://github.com/metabase/metabase) | |
 | Search (Mustang, Alexandria) |             | Elasticsearch, Solr, Lucene | [algolia](https://www.algolia.com/) |
-| pubsub | [pubsub](https://cloud.google.com/pubsub/docs/overview) | RabbitMQ, [PubNub](https://www.pubnub.com/) | AWS SQS/SNS, [AWS AppSync](https://aws.amazon.com/appsync) |
+| pubsub | [pubsub](https://cloud.google.com/pubsub/docs/overview) | NATS.io(https://nats.io), RabbitMQ, [PubNub](https://www.pubnub.com/) | AWS SQS/SNS, [AWS AppSync](https://aws.amazon.com/appsync) |
 | [Flume (Java)](https://ai.google/research/pubs/pub35650) | [Apache Beam](https://beam.apache.org/)            | [Apache Crunch](https://crunch.apache.org/) |     |
 
 ### DevOps