update CHANGELOG

CHANGELOG.md

@@ -81,6 +81,7 @@ IMPROVEMENTS:
   * provisioner/puppet-masterless: `working_directory` option [GH-1831]
   * provisioner/puppet-masterless: `packer_build_name` and
       `packer_build_type` are default facts. [GH-1878]
+  * provisioner/puppet-server: `ignore_exit_codes` option added [GH-2280]
 
 BUG FIXES:
 

website/source/docs/provisioners/puppet-server.html.markdown

@@ -51,6 +51,9 @@ required. They are listed below:
 * `facter` (object of key/value strings) - Additional Facter facts to make available to the
   Puppet run.
 
+* `ignore_exit_codes` (bool) - If true, Packer will never consider the
+  provisioner a failure.
+
 * `options` (string) - Additional command line options to pass
   to `puppet agent` when Puppet is ran.