Added Doc description (#155)

* Doc description

Added proper doc description
Took couple of lines from Discourse

This is just a temporary measure
Excpect Discourse doc to override this when ready

* cloud / cluster

Changed cloud to cluster

metadata.yaml

@@ -2,7 +2,7 @@
 # See LICENSE file for licensing details.
 name: mlflow-server
 description: |
-  MLflow
+  mlflow is a Kubernetes charm bundle for MLflow. This bundle automates the deployment and operation of MLflow on any Kubernetes cluster.
 summary: |
   A charm which provides a Kubernetes installation of the MLflow (https://mlflow.org/) server.
 docs: https://discourse.charmhub.io/t/mlflow-server-docs-index/10816