feat: add droneci module

- add droneci module for server
- add droneci/server role
- add consul query for droneci service
- manage certificates, ssh principals, consul services/checks

modules/droneci/templates/droneci_env.erb

@@ -0,0 +1,3 @@
+<% @env_vars.each do |key, value| -%>
+<%= key.upcase %>=<%= value %>
+<% end -%>

modules/droneci/templates/droneci_service.erb

@@ -0,0 +1,20 @@
+[Unit]
+Description=Drone CI Service
+After=docker.service
+Requires=docker.service
+
+[Service]
+ExecStart=/usr/bin/docker run --rm \
+  --name=drone \
+<% @ports.each do |port| -%>
+  -p <%= port %> \
+<% end -%>
+<% @volumes.each do |volume| -%>
+  --mount <%= volume %> \
+<% end -%>
+  --env-file <%= @env_file %> \
+  <%= @docker_image %>
+Restart=always
+
+[Install]
+WantedBy=multi-user.target