Add functionality to disable the zack/r10k webhook

Prior to this commit, if you upgraded from a previous version of
the control-repo both code manager and zack/r10k webhook would
be running and ready to receive data.  This can present problems
if the webhook isn't disbled in the git management system is
sending data to both receivers.

This commit adds rudimentary ability to break the zack/r10k
webhook so it can't receive data.

Author: npwalker

site/profile/manifests/git_webhook.pp

@@ -6,6 +6,7 @@
     include profile::git_webhook::zack_r10k_webhook
   } else {
     include profile::git_webhook::code_manager
+    include profile::git_webhook::zack_r10k_webhook_disable
   }
 
 }

site/profile/manifests/git_webhook/zack_r10k_webhook_disable.pp

@@ -0,0 +1,14 @@
+class profile::git_webhook::zack_r10k_webhook_disable {
+
+  file { '/etc/webhook.yaml' :
+    ensure => absent,
+    notify => Exec['stop and disable webhook service'],
+  }
+
+  exec { 'stop and disable webhook service' :
+    command     => '/opt/puppetlabs/puppet/bin/puppet resource service webhook ensure=stopped enable=false',
+    logoutput   => true,
+    refreshonly => true,
+  }
+
+}