feat: add vmcluster module (#363)

- manage vmstorage package, service and environment file
- manage vmselect package, service and environment file
- manage vminsert package, service and environment file
- manage vmagent package, service and environment file
- manage options for vmstorage, vmselect, vminsert, vmagent role

Reviewed-on: #363

modules/vmcluster/templates/vmagent.scrape.yaml.erb

@@ -0,0 +1,37 @@
+global:
+  scrape_interval: 15s
+  scrape_timeout: 10s
+
+scrape_configs:
+  - job_name: 'consul'
+    consul_sd_configs:
+      - server: 'consul.service.consul:8500'
+        token: <%= @consul_node_token %>
+        scheme: http
+
+    relabel_configs:
+      # Only keep services with the `metrics` tag
+      - source_labels: [__meta_consul_tagpresent_metrics]
+        regex: true
+        action: keep
+
+      # Use the service address and port
+      - source_labels: [__meta_consul_node, __meta_consul_service_port]
+        separator: ':'
+        target_label: __address__
+        replacement: '${1}:${2}'
+        action: replace
+
+      # Set scheme to metrics_scheme
+      - source_labels: [__meta_consul_tag_metrics_scheme]
+        target_label: __scheme__
+        action: replace
+
+      # Set path to /metrics
+      - target_label: __metrics_path__
+        replacement: /metrics
+
+      # Use metrics_job=<job> as job label
+      - source_labels: [__meta_consul_tag_metrics_job]
+        target_label: job
+        action: replace