feat: create exporters module (#364)

- upgrade node_exporter, bring managed under exporters module
- upgrade postgres_exporter, bring managed under exporters module
- add flag to cleanup previous iterations of exporters from prometheus module
- fix issues with vmclusster: replication + dedup

Reviewed-on: #364

hieradata/roles/infra/metrics/vmselect.yaml

@@ -7,8 +7,9 @@ vmcluster::vmselect::data_path: /data/vmselect-cache
 vmcluster::vmselect::options:
   search.skipSlowReplicas: 'true'
   search.denyPartialResponse: 'false'
-  replicationFactor: '2'
-  globalReplicationFactor: '2'
+  replicationFactor: '5'
+  globalReplicationFactor: '3'
+  dedup.minScrapeInterval: 15s
   tls: 'true'
   tlsCertFile: '/etc/pki/tls/vault/certificate.crt'
   tlsKeyFile: '/etc/pki/tls/vault/private.key'