fixes #6445 - Configure external authentication via FreeIPA.
fixes #3185 - refresh proxy features when foreman_smartproxy notified
Configuration in YAML

This patch moves configuration to /etc/puppet/foreman.yml. By moving the
configuration into a settings file, we can use external_node.rb and
foreman-report.rb as plain files.

This is based on a patch by @frimik.
Move foreman::config::enc into foreman::puppetmaster