puppet: Run GitHub Camo on lb0 for external-content.zulipcdn.net.

(imported from commit c03f2018fee1d88b747f45fc7841949f61e5c06c)

servers/puppet/modules/zulip/files/camo_defaults

@@ -0,0 +1,3 @@
+ENABLED=yes
+PORT=9292
+CAMO_KEY=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

servers/puppet/modules/zulip/files/nginx/sites-available/loadbalancer

@@ -91,3 +91,15 @@ server {
         include /etc/nginx/humbug-include/loadbalancer;
     }
 }
+
+server {
+    listen external-content.zulipcdn.net:443;
+
+    ssl on;
+    ssl_certificate /etc/ssl/certs/external-content.zulipcdn.net.combined-chain.crt;
+    ssl_certificate_key /etc/ssl/private/production-zulipcdn.key;
+
+    location / {
+        proxy_pass http://127.0.0.1:9292/;
+    }
+}

servers/puppet/modules/zulip/manifests/loadbalancer.pp

@@ -34,4 +34,16 @@ class zulip::loadbalancer {
     target => '/etc/nginx/sites-available/loadbalancer',
   }
 
+  # Config for Camo
+  $camo_packages = [ "camo",]
+  package { $camo_packages: ensure => "installed" }
+
+  file { "/etc/default/camo":
+    require => Package[camo],
+    ensure => file,
+    owner  => "root",
+    group  => "root",
+    mode => 644,
+    source => "puppet:///modules/zulip/camo_defaults",
+  }
 }