Update README (#588)

List some components, make it sound less unfinished.

README.md

@@ -1,11 +1,18 @@
 # Grafana Dskit
 
 This library contains utilities that are useful for building distributed
-services.
+services, including:
+ - Exponential [backoff](https://github.com/grafana/dskit/tree/main/backoff) for retries.
+ - A common [cache](https://github.com/grafana/dskit/tree/main/cache) API, implemented for Memcached and Redis.
+ - [Hedging](https://github.com/grafana/dskit/tree/main/hedging), sending extra duplicate requests to improve the chance that one succeeds.
+ - A common [key-value](https://github.com/grafana/dskit/tree/main/kv) API, implemented for Consul, Etcd and Memberlist.
+ - RPC [middlewares](https://github.com/grafana/dskit/tree/main/middleware), for metrics, logging, etc.
+ - A [services model](https://github.com/grafana/dskit/tree/main/services), to manage start-up and shut-down.
 
 ## Current state
 
-This library is still in development. Continuously moving utilities from the all the Grafana database-related projects.
+This library is used at scale in production at Grafana Labs.
+A number of packages were collected here from database-related projects:
 
 - [Mimir]
 - [Loki]