message: Improve Cluster section of Readme
diff: @@ -371,7 +371,27 @@ To find an examples please refer to [examples](./examples/server_events.rs).
  ### Cassandra clusters and load balancing
  -CDRS supports Apache Cassandra clusters and load balancing.
  +CDRS supports Apache Cassandra clusters and load balancing. In order to connect
  +to desired nodes you have to provide related transports (either TCP or TLS)
  +and to configure r2d2 pool.
  +
  +```rust
  +let cluster = vec![_ADDR1, _ADDR2]
  + .iter()
  + .map(|addr| TransportTcp::new(addr).unwrap())
  + .collect();
  +let config = r2d2::Config::builder()
  + .pool_size(15)
  + .build();
  +```
  +After that you need to choose desired load balancing strategy and instantiate
  +cluster collection manager. At current moment
  +two static strategies were implemented: `Random` and `RoundRobin`.
  +```rust
  +let load_balancer = LoadBalancer::new(cluster, LoadBalancingStrategy::RoundRobin);
  +let manager = ClusterConnectionManager::new(load_balancer, authenticator, Compression::None);
  +```
  +After that you'll be able to communicate with cluster via r2d2 connection pool.
  ### Supported features
  - [x] lz4 decompression
  @@ -457,7 +477,12 @@ Running Cassandra on Local
  2. If docker is new to your tool set; it is never too late to know this awesome tool https://docs.docker.com/docker-for-mac/
  + Running Cassandra Cluster on local
  + -----------------------------------
  +To start Apache Cassandra cluster on local just run `tests/build-cluster.sh`.
  +This script will create two nodes of Apache Cassandra 3.9 with following exposed
  +ports: 9042 and 9043.
  ### License
  