Fix typo in README

Author: DifferentialOrange

README.md

@@ -8,7 +8,7 @@
 
 1. Install jsonnet package dependencies with ```jb install```.
 
-## Experimantal cluster
+## Experimental cluster
 
 ```docker-compose up -d``` will start 5 containers: Tarantool, Telegraf, InfluxDB, Prometheus and Grafana, which build cluster with two fully operational metrics datasources (InfluxDB and Prometheus), extracting metrics from Tarantool instance. We recommend using the exact versions we use in experimental cluster (e.g. Grafana v6.6.0).