Documentation: add Grab etcd use case

Documentation/production-users.md

@@ -156,3 +156,15 @@ In [hyper.sh][hyper.sh], the container service is backed by [hypernetes][hyperne
 - *Backups*: None, all data can be recreated if necessary.
 
 [shafreeck]:https://github.com/shafreeck
+
+## Grab
+- *Application*: system configuration for services, service discovery
+- *Launched*: June 2016
+- *Cluster Size*: 1 cluster of 7 members
+- *Order of Data Size*: megabytes
+- *Operator*: Grab, [taxitan][taxitan], [reterVision][reterVision]
+- *Environment*: AWS
+- *Backups*: None, all data can be recreated if necessary.
+
+[taxitan]:https://github.com/taxitan
+[reterVision]:https://github.com/reterVision