Cluster support for clickhouse

[pheepa]

Feature description

ALTER, CREATE, DROP queries in multiple nodes Clickhouse setup should include "on cluster <cluster_name>" clause to run query on all nodes in cluster.
Now it seems that it has not been implemented.

Are you a dlt user?

I'd consider using dlt, but it's lacking a feature I need.

Use case

Correct work with multiple nodes setup

Proposed solution

on_cluster_mode and cluster_name added to clickhouse.credentials
all ddl parameterised with "on cluster"

Related issues

#1183