Deploy zerotier-3 on DO

Changes the firewall config to allow the control UI to be reached from
all connected networks.

site-cookbooks/kosmos_zerotier/recipes/zncui.rb

@@ -28,11 +28,13 @@ end
 
 include_recipe 'kosmos-base::firewall'
 
-if node['ztncui']['http_allow_access_from']
-  firewall_rule 'zncui_http' do
-    port     3000
-    protocol :tcp
-    command  :allow
-    source   node['ztncui']['http_allow_access_from']
+if ip_addresses = node['ztncui']['http_allow_access_from']
+  ip_addresses.each_with_index do |ip_address, i|
+    firewall_rule "zncui_http_#{i}" do
+      port     3000
+      protocol :tcp
+      command  :allow
+      source   ip_address
+    end
   end
 end