Make more installation configurations available

[z9r5]

All clusters are different: bare metal, GCE, AWS, Azure… There should be several installation configurations:

• ClickHouse with local index on each node. Best option for bare metal; it lowers network delays between fluentd and ClickHouse;
• ClickHouse as a cluster. Best option for cloud based K8s (GCE, AWS, Azure);
• Standalone ClickHouse. For small K8s clusters or testing purposes. ClickHouse is installed on single node while fluentd is placed on each node.
• External ClickHouse. ClickHouse is installed outside the cluster and is used as an external service while fluentd and dashboard are installed in the cluster.

[diafour]

More feedback about installation:

• helm should not be required

[trusch]

:+1: A helm-less install would be much appreciated.

[diafour]

• clickhouse setups not managed by loghouse chart:
  • external clickhouse cluster addressed by a hostname (ExternalName?, ha proxy?)
  • internal clickhouse in its own namespace

related to https://github.com/flant/loghouse/issues/146